Dear Dhiraj, In 2018, under State Quota, 562 marks secured a seat in North Delhi Muncipal Corporarion Medical College under General Category. That was the cut off. With 577, it is a very close call. Coming to Bihar, 533 was the cut off. So your son has better chances in Bihar.  Having said that, cut offs change every year and are dependant on various factors like no.of seats available, no.of candidates appearing for the exam, top NEET score and difficulty of the exam. You can also use our College Predictor services to check your options:
https://medicine.careers360.com/neet-college-predictor?utm_source=google-search&utm_medium=paid&utm_campaign=neet-clgpd