USA

Let me ask you, what kind of a job are you looking for?
Do you intend to pursue your career in engineering or planning to shift?
What are your interests?
The answer to these questions itself will help you decide which course you need to look out for. It is important you know what you want, figure out your own interests and career goals, check various job profiles, career outcomes and see what interests you.

Hi Uma, these universities are quite famous for the graduate program mass communication, please check the websites for admission and fee information
John Hopkins
Northwestern University
University of Utah
University of Oklahoma Norman Campus to name a few.

Hey Deep,
US admission process is holistic, nothing particular can assure you admission in US universities, they will look at your whole profile not just 12th marks but all the high school marks viz. 9th,10th,11th and 12th marks with your SAT and TOEFL marks and your ECs. So, you see this is a bit complicated process. Scoring high grades in SAT or 12th will not ensure you admission in the universities. You have to maintain your whole profile and show the university that you deserve the admission.
I hope you got me.

The course duration is 4 years.

Hi Sakshi,
While filling out the common application, simply follow the Indian system.

HI Suyash,
It is not a mandatory thing to do - however, best would be to be a part of an NGO to support your profile - concentrate more on your grades in India and your SAT/TOEFL Scores.

Hi Pankaj,
It seems Mr. Sanjay Kaushik has already answered your query.

Yes, but you need to know about the admission process of different countries. If you want to study your Master's in USA, you need to give GRE and TOEFL. If you want to pursue your Master's in other specified countries, then you must give IELTS or TOEFL and must maintain a good CGPA in your Bachelor's degree.
I hope it helps.