Hello aspirant

Your first target should be to achieve a good percentile in jee mains so that uh can secure a seat in some NIT , for that you should practice at least one test paper of previous year daily since there is very short amount of time is left in the upcoming attempt . Thoroughly revise your concepts and work on your strengths , that is all you can do for now . After achieving this you can follow the same suggestions for JEE advance with more focus on the approach of question solving

Hope my ans helps

Wish you All the very best!