Dear Student,

It totally depends on your preparation. If you know how to revise for your exam in 45 days there is no use to take the coaching but if you are totally confuse and don't have any idea you can go for the coaching institute.

In last 45 days you should focus on your revision. Give extra attention to the topics which carries more weightage in the exam. 

JEE Main is all about the practice so go through previous year papers, solve as much as MCQs for your practice and mock test series to analyze your preparation level to work on your strength and weakness.

Good Luck!!