Hi Suvarna!

I do not understand what you mean by business rules. If you want to know the rules and regulations of NEET counselling conducted by MCI, you can visit the official website.

Regarding OBC certificate, it should be issued by a competent authority. Kindly check out the information bulletin on the official website and search for "performa for obc candidates" on page 100 in the pdf.

Good lucj!