Dear Mithu, With 300 marks, you can qualify in NEET but not every qualified Candidate can get a seat. Your chances also change depending on the State you belong to. With 300, if you belong to Karnataka,, you can get a seat in a Private Medical College. But in States like Delhi, you cant get a seat with that score. So a lot depends on the State you hold the domicile of.

Hello Mithu,  NEET cut off get changes every year depending on various factors like number of students appeared for exam,  highest marks,  and many more things. So you have to decide average marks depending on previous years cut off. As per last year cut off students with more than 400 marks got seat in government medical college under SC category. So you have to prepare yourself to get more than 400 marks.

I hope it will help you.

Thanks.