Hello,

As you belong to general category, you're only required to have 50% aggregate in PCB inclusive of theory and practical, and you need to have studied Physics, Chemistry, Biology/Biotechnology and English as core subjects, attained 17 years as on 31st December of the appearing year, as of now there is no upper age limit as the decision is still pending in the Supreme Court, hence there is no restrictions in terms of number of attempts, however if you're enquiring this especially in regards to AIIMS, then yes candidates belonging to UR/EWS/OBC need to have 60% aggregate in PCBE, for SC/ST it's 50%, and also AIIMS doesn't allow biotechnology unlike in case of NEET UG eligibility criteria, for more details check out our page at https://medicine.careers360.com/articles/neet-eligibility-criteria