If you are a BSc student of 3 years course, then giving GATE in your BSc isn't at all beneficial for you. You should give this examination while you are in your MSc. Now if you are studying BSc (Hons) or BSc (General) then you can give the IIT JAM paper.

IIT JAM organizes the examination for the subjects:

• PHYSICS
• CHEMISTRY
• MATHEMATICS
• MATHEMATICAL STATISTICS
• BIOTECHNOLOGY
• GEOLOGY
• ECONOMICS

For the official website of IIT JAM visit :

https://jam.iitr.ac.in/

To know more about IIT JAM visit the link below:

https://university.careers360.com/exams/jam

I hope this answer helps. All the very best for your future endeavors!