Hello Aspirant ,
I assume you are asking about AIIMS ( All India Institute of Medical Sciences ) , class 12 marks are not required for admission in AIIMS and the admission is totally based on entrance exam called The National Eligibility cum Entrance Test Undergraduate (NEET UG) .
If you are a serious aspirant , you should focus on the NEET UG exam and try to get more than 60% marks in your boards .
For more details about NEET UG visit :
https://medicine.careers360.com/exams/neet
Hope this helps.
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