Hi student,

According to the eligibility criteria of JEE Main 2021, a student should have passed class 12 or qualifying the exam in 2019 or 2020 or is appearing in 2021, to be eligible to give JEE Main Exam. Now, you have passed class 12th in 2016, you are not eligible for JEE Main 2021.

Refer here for more info - JEE Main Eligibility Criteria 2021 - 75% in Class 12 (Relaxed), Check Age limit, Aggregate Marks (careers360.com)

Feel free to ask doubts in the Comment Section.

I hope this information helps you.

Good Luck!