Hey Abhimanyu,

Hope you are doing well!

Well dear,If you have been alotted a seat in AIIMS,and you want to participate in other rounds,then you just need to apply for second round.

You have to go to the institue only if you are sure of taking admission in it.Because,they will take your migration certificate(original one),then you can't apply somewhere else.

Hope This was helpful!

All the best!

Keep Smiling :)