MBA Entrance Exam

For MBA , it really doesn't matter if you are from ISBS or IIMP because the placements are centralized. Ultimately when you sit for placements what matter is if you meet the company's criteria. They consider all campus of Indira as the same. And for them its Indira Group of Institutes and not ISBS or IIMP. So you can go ahead and confirm your seat in which ever campus it is that you are getting admission. Let me know if there is anything in particular that you want to know. I hope that helps.

the cut off cat is around 90 to 100 percentile for best business school and for mat it is around 600 to 750 marks.

Dear Debmalya,
No Working with NGO wouldn't be considered as work experience when you will go for admission in business schools, though the gap of 2years won't affect your chances of admission.
Business schools ask for justification if gap is of 3 years or more,
All the very best

Cutoff for CET is 99.2X percentile and for CMAT is 99.9X percentile.

I recommend anything above 95 will land you to premier B-School, On safer side you need 90 minimum so you can get top 30bschools. Also a good GDPI score will land you with low entrance exam score.

Criteria is mentioned below.Please refer.
https://www.shiksha.com/mba/exam/nmat
You need to give more n more mock exams and identify your weaknesses and rectify them to get good score.

You need to prepare for CAT exam from TIME, IMS coaching when you are in the third year. You find difficulties in solving CAT papers of previous years, you need the help of Arun Sharma CAT books , and you must study your papers in graduation. You just need four hours to seven hours a day for CAT study. Best of luck.

for time it is around 40,000

MHCET is not compulsory in Maharashtra, every college has their own requirements ij terms of entrance exams. Sydenham is the best to pursue MBA, under your budget, Although You wont get International Trade specialization. Flame, BIMM, are other good coll as well.
You can Try Kjsomaiya and Welingkar for your specialization if you are ready to shell out 10lacs.
https://www.shiksha.com/mba/ranking/top-mba-colleges-maharashtra-accepting-mat/2-0-114-0-306

It is 99.99 percentile.