With 512 you seem to have a fair chance but it depends a lot on your state. The marks required to get admission in a medical college through NEET varies a lot according to your category and quota. The cut off varies a lot in different states under the State quota and well the All India quota. Hence your category, state etc would determine the marks required by you to a lot of extent. But according to the previous year trends, for admission in a government medical college under the State quota a score above 510 would safe.

For more information you can visit  NEET Rank Predictor

https://medicine.careers360.com/neet-rank-predictor?utm_source=qna&utm_medium=neet_rp

For more information you can visit NEET College Predictor

https://medicine.careers360.com/neet-college-predictor?utm_source=qna&utm_medium=neet_cp

I hope this information helps you.

Good Luck!!