Hi Neha 

To qualify neet examination for OBC candidate you must score marks greater than 40 percentile but that would not suffice for getting a goverment medical college. 

For geeting a seat in goverment medical college you must aim to score around 550 to ensure your selection of seat through All India Quota (AIQ).

Cutoff score of different state varies, scoring  marks greater than 520-530 may fetch you a seat through 85% state quota.

These marks are based on previous year trends and may vary this year depending upon difficulty of examination.

Hope this helps.