You have less chances in BITSAT based on your marks.

You can get admission in private colleges through JEE Main. You can get private college in other states like: Haryana, UP, West Bengal, Punjab, Rajasthan, Maharashtra. Most of the states have reservation for other state students in private colleges based on JEE Main score/rank. You need to apply separately for them.

You can take admission in private colleges but if you are determined to take admission in NITs or IITs then you can take a drop.

Good Luck!!