Editing

Non-linear editing is a specialisation domain, and there may be many things that you will need to keep learning along with the production learning.
The suggestions that I can make are:
1. A degree in a popular language that shall be used in your works and place.
2. Content writing and proof reading.
3. Web development and digital marketing.
4. Music and sound mixing basics/audio production.
5. Advertising and public relations management.
The decision depends on how much time you get free from the work of learning documentary production. When you say that you are learning the production of documentary-I take it as a comprehensive work that is itself a time-taking thing and might not allow you to venture for more.

The Certificate you are pursuing in Editing and Proof Reading is a good way to join the Media jobs, as Content Writing and Content Editing-Proof Reading is quite a good career. From Media/Journalism Writings to Website Developments, this task has a role.
You may think of the following courses depending on the qualifications you already have:
1. If the current course is done after doing graduation then a Post-Graduation in Mass Communication/Mass Media/Media Production can also be good for you. I shall not hesitate to suggest even a Master Degree in A Language- English, Hindi or the one you see as an additional strength for editing and proofreading works.
2. If one does Certificate in Proofreading and Editing after class 12th, pursue Graduation as a must to do thing. Any Stream you may choose keeping in mind that an Alternative Career has to be met openly. Proofreading and Editing Job can also be a part-time thing so you have enough time to do another degree or Higher Studies.
3. If this Certificate Course is done by someone who is a Master Degree Holder, if not in Language or Social Science, Humanities, do one degree.

Editing and proof-reading (text related) are practically learned skills and shall need serious observation-based studies. The real learning not really possible in distance mode in the absence of a structured contact programmes. It is advised that some regular learning plan should assist in the distance mode learning which otherwise is not good for courses of media-editing or proof-reading. I am still not denying that distance learning cannot teach the above two things. If you would have meant video editing then there would have been a strong no to distance mode.
It is not worth doing any course which needs professional competence which is developed by personal contact with the institution and in regular classes.
There are many aspects of media-related courses and it should be clear to us that distance learning cannot develop the level of skills and competence that regular courses can do.
It is possible that one does distance learning studies when a foundational skill-set is already earned.
Please refer to the following replies as the same type of response is needed here as well (read your query subject in place of performing arts or editing):
Distance learning was not devised as an alternative to classroom learning or practical learning with the teachers.The same applies to the question as well. FCP is something which is a special learning and through the distance mode, I do not think that it is possible to comprehend and learn the best of FCP like tool through distance. Besides, in India, we do not have that strong and fault-free delivery system of distance learning programmes.

Dear Learner,
Distance learning was not devised as an alternative to classroom learning or practical learning with the teachers. The same applies to the question as well. FCP is something which is a special learning and through the distance mode, I do not think that it is possible to comprehend and learn the best of FCP like tool through distance. Besides, in India, we do not have that strong and fault-free delivery system of distance learning programmes. Read the related advice: Is it worth to pursue a certificate course in non-linear editing from distance learning in India and why? The question has two sides to answer- Is it worth to do a course of this kind via distance learning and the other side is should it be done from India? Let us discuss the first thing first.
1. Linear editing is a thing of the past in this digital and technology-led age. Hence, it is the non-linear editing that remains the way video production is done for all the forms of films, documentary, TV serial or music videos, etc. Even news reporting videos are also customised. Seeing the demand for this task and knowing the essentials and challenges, it is not advisable or suggested that one should go for a no classroom model of learning "editing" of any kind and level. Distance learning, anywhere in the world it is, has its limitations. There are virtual platforms and ways like video conference, classes, etc. Or MOOCs that offer such learning. But, we must understand that the actual learning of skill through practical and hands-on while doing the course. If the place offers somewhat like near-regular classes or the student arranged for himself some training then only the distance learning course can do some good.
2. Based on the conclusion above, if the arrangement is made for proper practical training, then do it from India otherwise not. IGNOU offers some courses like this, other institutions might also offer, but it is not suggested to join a distance learning in this stream.

The same scope that is there for FCP and editing in government jobs is there for non-linear editing. Excerpts already on Shiksha (from my profile). An excerpt from the above written by me needs to be shared as an intro to the reply:
1. Linear Editing is a thing of the past in this digital and technology-led age. Hence, it is the Non-Linear editing that remains the way video production is done for all forms I.e. films, documentary, TV serial, music videos, etc. Even news reporting videos are also customized. The career prospects for a certificate course are not that high, even in India or abroad. But, the condition in this skill and creativity, innovation-based job profile will decide the success of the candidate. If one is skilled enough to match the professional acumen of degree or Master's degree holders in production skills, the job and career is going to be good. If there is a delay in getting the same course recognised and noted, the person has to work very hard and do some good work to be shown as a portfolio. Career prospects are good, both in India and abroad.
https://ask.shiksha.com/is-it-worth-to-pursue-a-certificate-course-in-non-linear-editing-from-distance-learning-in-india-and-why-qna-4392987
https://ask.shiksha.com/what-are-the-government-job-opportunities-after-completing-a-course-in-camera-and-lighting-qna-4393105
https://ask.shiksha.com/what-are-the-government-job-opportunities-after-completing-a-course-in-pro-fcp-and-editing-qna-4393119.

A Course in Pro-FCP video editing is itself an accomplishment and certainly has much scope for work. As the video editing work has become as important as the whole production project of that work. The certified FCP Editor can get good opportunities in the government departments as well.
1. Doordarshan
2. Advertising and PR (Information)
3. Cultural and Youth Affairs
4. Sports Departments
5. Media Agencies of the Government or Semi-government.
Also read: https://ask.shiksha.com/what-are-the-career-prospects-in-india-and-abroad-for-certificate-in-final-cut-pro-fcp-and-editing-qna-4393232
Final Cut Pro is the globally acclaimed and used software or tool to edit and make movies/films. As we all know and acknowledge that in India, there is a great demand for quality video editing because most of the mass media or filmmaking children are less exposed to the actual work they are required to do. FCP-If the candidate knows the know-how of the tool and possesses a certificate as well as a selling commodity for sure.
-Creativity
-Improvisation
-Quick Response Skills are the three major things needed in an FCP user. If these are present and the Final Cut Pro user is well-versed with the skills-shortcuts there are ample opportunities in production houses, news channels, filmmaking, local level production houses and educational Institutions, other than the ones teaching mass communication and media subjects, also demand people who are good at FCP because this is an age of MOOCs as well as virtual learning, smart classrooms have enhanced the demands of educational programmes. So this video editing software remains the winner all around. The certificate in FCP will certainly get one a job proving the skills and knowledge of FCP.

Mass communication is a media-related course whereas editing and proof reading are the small segments of the vast media careers. One needs to know that mass media is the comprehensive umbrella term and course that covers all leading segments and aspects of mass media. Whereas, proofreading goes for content check-content writing area. Editing also has two dimensions- Video editing and Content Editing for print media material. Mass media always has better scope in terms of variety of acceptance in careers. Proof-reading demands a specific opening and has limited offerings. Moreover, editing and proof-reading of language content are related to office communication and do have jobs with the government. However, this must be noted and should be known before an answer is supplied to this question, whether one is doing a degree in the subject or merely a Diploma. Company secretary and office secretary also need the skills taught in the purview of the course mentioned. This must be made clear that government jobs do not have this specific requirement but have this as one of the things needed in certain profiles. There are more jobs of SSC Clerk Grade and other Junior Staff or Clerk level jobs that one can access having the minimum eligibility of being a graduate. I must make it clear that in my observation as a mass communication expert, not a language expert for proofreading, there are more jobs in the private sector. Media, web development where content is written, publishing industry and service sectors have a scope.

Read this answer as well: https://ask.shiksha.com/is-it-worth-to-pursue-a-certificate-course-in-non-linear-editing-from-distance-learning-in-india-and-why-qna-4392987. An Excerpt from the above written by me needs to be shared as an intro to the reply:1. Linear Editing is a thing of the past in this digital and technology-led age. Hence, it is the Non-Linear editing that remains the way video production is done for all forms i.e. films, documentary, TV serial or music videos etc. Even news reporting videos are also customized. The career prospects for a certificate course are not that high, even in India or Abroad. But, the condition in this skill and creativity, Innovation based job profile will decide the success of the candidate. If one is skilled enough to match the professional acumen of Degree or Master's degree holders in production skills, the job and career are going to be good. If there is a delay in getting the same course recognized and noted, the person has to work very hard and make some works to be shown as a portfolio. Career prospects are good, both in India and abroad.

Final Cut Pro is the globally acclaimed and used software or tool to edit and make movies/films. As we all know and acknowledge that in India, there is a great demand for quality video editing because most of the mass media or film making children are less exposed to the actual work they are required to do. FCP-If the candidate knows the know-how of the tool and possesses a certificate as well is a selling commodity for sure.
-Creativity
-Improvisation
-Quick Response Skills are the three major things needed in an FCP user. If these are present and the Final Cut Pro user is well-versed with the skills-shortcuts there are ample opportunities in production houses, news channels, filmmaking, local level production houses and educational Institutions, other than the ones teaching mass communication and media subjects, also demand people who are good at FCP because this is an age of MOOCs as well as virtual learning, smart classrooms have enhanced the demands for educational programmes. So this video editing software remains the winner all around. The certificate in FCP will certainly get one a job proving the skills and knowledge of FCP.