Music

Yes you can apply for admission. For admission in Diploma program, you need to have passed 12th from a recognized board.

Same criterion is applicable for all candidates . 45% or more in aggregate marks including music as one of the subject in 10+2 .

Yes, you can get a degree if you have taken admission in this course through a recognized college.
But it is always advisable to go for a regular degree and attend classes in order to have a good understanding about the course.

Why not? India is a land of rich culture. Why do you think that you cannot? Nothing is impossible if you have a good sense of music, definitely, you will be a successful singer. You can work both in India and overseas. First, you decide in which field do you have interest then you go for that.

It is always good to pursue a course in which you have a keen interest. You can go for BA (Hons) in classical music.

Hello Suraj,
Some of the best colleges for Music in the world today are Berklee College of Music, The Royal Academy of Music etc. Here are some more: http://www.onlineschoolscenter.com/posts/20-prestigious-music-degree-programs-world/
Visit websites of the colleges to know about the application process.

Hello Krishna,
Of course yes. You can pursue your graduation in music after completion of 12th.
Best wishes