will I get deemed university in tamilnadu like cheetinad srm Ramachandra meenakshi saveetha with around 300 neet score?

Yes. You have good chance to get saveetha, meenakshi, chettinad… you can install mbbscouncil app to check the actual last year cut off for these colleges. also there is a video lecture in the app under “counselling courses” menu which describes how to go about taking admission in private colleges especially deemed universities. all the best.