Hi Sharmila

See, the cutoff varies every year, so there's no such thing like this much marks will 100% percent get you a medical seat. But, approximately, in NEET 2020 for SC category getting a government medical seat, you need to secure atleast 200-380 marks. 

Rest, aim to secure higher marks in NEET. 

I hope this information proves helpful to you. 

All the best