Hello Aspirant,

For such national level entrance examinations like JEE-Main, JEE-Advance, NEET one should devote at least 2 months to only solving previous year question papers, sample papers and mock tests because solving such tests enhances the self confidence of candidate as well as it is the wise strategy to revise complete syllabus. So you should try to complete your JEE syllabus by December 2021 because then in March-April you will have to appear for your boards as well.

You can download different previous year's question papers and sample papers of JEE-Main from the link given below :-

https://engineering.careers360.com/articles/jee-main-sample-papers

https://engineering.careers360.com/articles/jee-main-question-paper

You can also check out our JEE-Main Learner's program which  includes the full length Mock test series  and you check out this from the link given below :-

https://learn.careers360.com/knockout-jee-main-april/?product=27

NTA has also given the facility for mock test which you can give from the link given below :-

https://nta.ac.in/Quiz

I hope this information helps you.

Good Luck!!