Dear aspirant hope you are doing well. For general category candidate, 550 score is not good enough to get government medical college. Yes you have chance of getting private medical college. To get government medical college a candidate must score minimum 610+ for general, 580+ for obc , 480+ for sc and 420+ for St category student.

You can check out the previous years cut off bihar mbbs government medical college.

https://medicine.careers360.com/articles/neet-cutoff-bihar/amp

To know the  list of medical college with detailed report according to your score, you can use neet ug college predictor tool. Link is given below.

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

Hope it's helpful