If you have atleast 45% in your 10+2 (for reserved candidate 40%) and you have the Physics and Mathematics as compulsory subjects and any one subject from subjects from Chemistry / Biology / Biotechnology / Technical Vocational Subject / Electronics / Computer Science / Information Technology / Geology / Statistics in their class 12, then you are eligible for OJEE for the admission of Engineering and Architecture courses.

Also if you are student who will be appearing for 12, in that year you are also eligible to write OJEE provided you have to satisfy the eligibility as your result is released.

To know more you may visit the link provided below:

https://engineering.careers360.com/articles/ojee#OJEE-Eligibility-Criteria-2021

I hope my answer helps. All the very best for your future endeavors!