Engineering Entrance Exam

You need to score a decent percentile (Above 98 percentile), as most students appearing in GATE are from CS stream.

Yes of course, GATE (Graduate Aptitude Test in Engineering) is for the admissions into IITs and other reputed colleges for M.Tech or ME courses.

All IITs use Graduate Aptitude Test in Engineering GATE score for admissions to various post-graduate education programs (e. g. Master of Engineering, Master of Technology, Doctor of Philosophy). There is no direct admission in higher studies at IITs except for sponsored candidates.

Every IIT has it's own cutoff for admission in different branches.
So, I suggest you to score more as much as you can.
Do hard work and try to solve the paper correctly and less mistakes.
Just check the cut- off for the IIT
You can see the cut-off that is so high
Just concentrate on your studies and focus.

You must specify which course you want to pursue and the stream in which you are interested.

Yes, you can surely apply for the same. You should always have all the options handy with you.

It is very hard to guess the OBC rank. It is given by WBJEE only on the result portal.

With low score in JEE Mains you will not get the good colleges as in government colleges but you can contact to private colleges.

There is no chance in NIT with this percentile in JEE Mains.