There are very few chances of getting internship at AIIMS , New Delhi on merit basis.You need to apply well in advance and arrange for some source that can help you getting this internship.

Mostly you can do internship in AIIMS only if you have done your MBBS from AIIMS itself . They offer chance to external students only if there is some vacancy . So the chances are very low. But give it a try maybe your luck and hardwork help you grab this opportunity.