Hey,

Based on previous year data, with 500 marks you may get a rank between 92665-101137. You can also predict your rank using NEET Rank Predictor

According to previous year cut off, you cannot get government medical colleges through All India Quota. I saw that you are from Maharashtra. Based on the 2020 allotment, you can get a seat Vedanta Medical College, Palghar under OBC category through Maharashtra State Counselling. Other than these, you can surely get management quota seats in deemed universities. To get a complete list of colleges in which you can get a MBBS/BDS seat, you can use NEET College Predictor https://medicine.careers360.com/neet-college-predictor

Keep in mind that nothing fixed can be said until NEET 2021 results come out. Cut offs and ranks vary every year depending on the difficulty level of the paper, the number of seats available and performance of the students.