Hello

There's no more AIEEE exam now , long ago AIEEE examination got replaced by JEE Mains examination.

Now, there's no percentage barrier to be eligible for JEE mains

To be eligible  for JEE mains 2021 for BE or Btech you must be either appearing for 12th board exam in 2021 or should have passed it in 2020 or 2019 with Physics,  mathematical  and anyone of Chemistry or Biology or Biotechnology or Technical Vocational Subject.

But yes,

To be eligible for NITs, IIITs, IITs, GFTIs one needs at least  75% marks in aggregate in class 12 if belong to general or obc category or at least  65% marks if belongs to SC/ST or  must be in the top 20 percentile in  your class 12 th examination

For detailed information go through

https://engineering.careers360.com/articles/jee-main-eligibility-criteria

Thankyou