Hi,

It is advisable to prepare for entrance exams along with boards examinations as almost all colleges either conduct their own entrance exams like BITS, VIT, SRM, KIIT etc. or they accept students on the basis of JEE Mains or other state level examinations. Since, you have studied for your boards then you can study extra for the examinations too. Prepare for the entrance exams taking in consideration the examination pattern, syllabus, and topics wise weightage. Also, currently April and May session for JEE Mains have been postponed thus, you have time to prepare.

Here is a link that you can refer for tips to prepare for JEE Mains: https://engineering.careers360.com/articles/jee-main-preparation-tips#:~:text=Some%20of%20the%20valuable%20JEE,basis%20to%20name%20a%20few.

I hope this helped you.