Interior Design

You can only pursue undergraduate Diploma after completing class 10th from colleges like ITI. An undergraduate Diploma wouldn't help you much in your professional career. It is better if you complete your class 12th in whatever stream you like and then apply for a Bachelor's programme:B.Des in fashion designing or in interior designing or lifestyle and accessory designing or whatever you would love to.
A Bachelor's programme will give you a better understanding about design, and also you will have much better career prospectus. That will enhance your skills as a professional designer, so that you can get good job opportunities. Every well recognized college of design conducts campus placements. After doing a Bachelor's degree, you will easily get a package of INR 3 Lacs per annum.

After completing Master's degree in fashion design, one can apply for the post of Professor, Associate Professor or Assistant Professor in National Institute of Fashion Technology. The candidate must also have around 3-years of post qualification experience in teaching/ research at universities and institutes of national and international level in the relevant area and industry.
For recruitment information, one can visit:
http://www.nift.ac.in/aprecruitment for more details.
Other than NIFT, there are other teaching opportunities in reputed government universities and polytechnical colleges like NID, FDDI, etc.
Being a part of textiles committee under Textile Ministry of India is another option for those who want to pursue government sector. http://textilescommittee.nic.in/about-us/about-us tells about all the positions that can be taken up in the related field.