Exam

If you are able to score 120 or more in JEE Mains and above 75% in boards, then there is nothing to worry. You will get admission in a good government college. If you score more than 250, you may get admission in NIT.

GATE has three benefits:
1. Entry to PSUs.
2. Entry to top level institutes for M.Tech.
3. Scholarship of 12000 per month, if you take admission in Government College for M.Tech.
But, your GATE score must be good to get any of the above.

No, waiver of fee on the basis of percentile is not applicable. Yes, there may be some chances if you belong from reserved category (maybe).
Admission in IP will be made on the basis of rank obtained in CET i.e common entrance test.

Yes it is very much important to take these exams. Actually when you prepare for these exams you get to know and analyse things in a better way or it will be accurate to say in a logical way. That is very much required in a corporate world. So these exams test your reasoning and analysis capacity. S

MAT December is not accepted for admission into SIMSREE. February MAT is accepted, the cutoff for which is 99.96 percentile.

You can not join IIMA without appearing for CAT examination.