IIM

There is no official document which states the fact. If you consider for the interview purposes, maybe some people might have a bias. But the interviewers of IIMs are experienced enough to not let these biases affect the decision making.

I would suggest that you write a mock CAT to figure out your strengths and weak areas. Depending on your score you can figure out when to start preparing. Its possible to score well in CAT by preparing rigorously for 4-5 months if your basics are good.
Know more about CAT at :
https://edudrona.com/common-admission-test-cat/#1464927769900-a0617f54-da37/?mref=tanu

Dear mohammad sahib. iim s require minimum 90 percentile to secure. top iims require 95% percentile. so therefore try with other business schools. all the best.

at least 98 if you are general and if you have good academics and work experience 1-2 percentile difference might be there.

I don't think you will receive GDPI call from IIMs with 82 percentile in CAT. You will have to do really well and score atleast 99.5 percentile to get GDPI calls from atleast few older IIMs. Please understand that on an average 2 lakh students appear for CAT and 82 percentile means there are 36,000 students who have scored more marks than you. Seats in all IIMs combined is not more than 2000.

IIMs are institutes of higher learning in the field of management. IIMs offer PGDM equivalent to MBA. No IIM offers BBA degree.

Yes you can think about it. Initially try to develop habit of reading English newspaper. Mug up word and then take guidance from coaching or friends.

As soon as you complete your second year you can start your preparation for CAT and focus on your English and mathematics.

You have to just focus on CAT and other related exams.