Hello Ritam,

Yes you can definitely take the time for prepation of this entrance if you really want to take admission in a good institute such as IIT.

But this is not that easy so you have to be focused and constistent in your prepations.

In order to get good guidance for the prepation of the same you can also join Entrance 360 online crash course for JEE main and Advance where you will get number of video lectures, test series and much more from the experts.

To register for this course you can visit link given below,

https://www.entrance360.com/knockoutfull-jee-main-april/?utm_source=qna&utm_medium=announcement&utm_campaign=knockoutfull-jee

In order to download free sample papers for JEE you can visit following link.

https://www.google.com/amp/s/engineering.careers360.com/articles/jee-main-syllabus/amp

All the Best.

Hello Ritam,
Yes, of course if you have studied sincerely in 11th & 12th class.
Some tips could be helpful for you in the preparation of the JEE exam are given below-
Your basics in Physics, Chemistry & Mathematics should be very clear upto 12th std. You should read the NCERT books for basics. Then HC Verma for Physics, RD Sharma for Mathematics, OP Tendon for Physical & Inorganic Chemistry, and Organic Chemistry of "Arihant Publication" for detail or extra knowledge. 
You should also try to solve the previous years question papers, this helps too much and you should also give the mock test to rectify yourself and build your confidence level.
For preparation of exam, the most important thing is your confidence after that you should know the whole syllabus and make your plan properly for learning new chapters, solving the numericals and revision. All three things should be the part of your preparation strategy in daily routine.
The main thing is that you have to build your concentration level, then only you can stay focused on your goal. I would like to say that please limit the study time between 10 to 12 hours and please increase your concentration and speed of reading, understanding and solving the problems then you will not face any kind of difficulty.
For more preparation tips, importants topics & books, you can go through the link given below
Https://engineering.careers360.com/articles/jee-main-2019
In this way, you can prepare well for the JEE Main and the JEE Advanced.
Thanks for query on this platform, you may visit again for further queries.
All the best.