i got 86% in 10^th board and 82% in 12^th exam . how much do i have to score to qualify jee mains ??

First of all everything is relative, if there are many students gettting more than you, they will obviously be preferred.

Secondly, you have a good score in board exam both in 80’s but there are people out there who have both in 90’s. So you have to atleast score higher in JEE mains to overtake them to secure a seat.

I hope this is clear!