Hiba, now according to ESI C rules for admission to Medical Colleges under IP Quota, it doesn't matter which group the Insured belongs to. The opportunities are equal. Now IP Quota seats are filled under All India Quota by the DGHS on behalf of the NMC. Now AIIMS and JIPMER seats are also filled through All India Counselling. You can certainly apply  under IP Quota but the fact is unless you really score excellent marks, a seat in AIIMS will be difficult. Anything less than 650 cannot get you a seat in AIIMS because AIIMS has no IP Quota yet. Usually the IP Quota seats are filled in the mop  up round and by the most branches of AIIMS will be filled up. Even with OBC reservation, you will still need nothing less than 650.