If you pursue your MBBS from AIIMS Nagpur and hold a valid Maharashtra domicile certificate you are eligible to apply under the Maharashtra state quota for postgraduate medical admissions such as NEET PG. AIIMS Nagpur is a central government institute whose clinical training is recognized nationwide. For PG admissions under the state quota in Maharashtra the key requirement is your domicile status rather than your undergraduate institute. So as long as your domicile is Maharashtra and you meet NEET PG eligibility you can participate in the Maharashtra state quota counselling.