hi biton,

Firstly, New Business don't need a MBA degree.

MBA stream very much depends on your interest.
If you are good in accounting, go for finance stream, after completing degre in finance,
you can start a business like a finance consultant or a wealth managment experts.
You can also partener with a CA and start writing accouts for small businesses.
I think finance stream which forms backbone of any business should help you.
You can give second preference to supply chain management. Other MBA streams say
marketing and human resource can be learnt intuitively without attending lectures in classroom.

I hope this answer will help, all the best for the future!!!