Hello aspirant

518 is good score, but it is difficult to say that you will get admission in government college or not.

It depends upon cut off neet 2020 which will be released soon.  Till then we can rely on previous year's cut off. Cut off depends upon number of candidates appeared and qualified in exam, difficulty level of exam and previous year's cut off.

However for College prediction, following link may help you

https://medicine.careers360.com/neet-college-predictor