Yes,you are eligible if you have passed 12.
In eligibility criteria it says that candidate must have scored( for aiims) :

For General and OBC aspirants  60% aggregate;
For SC and ST candidates  50% aggregate

For PwD candidates - 45% aggregate
Your main aim should be to score more than 60% in every subject to take safe side because these government organization may change there eligibility from time to time if there is any need.

Hopes my answer was helpful.
If you have any more doubt check there official website.

JIPMER Puducherry

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