CBSE 10th

You need to complete HSC or a Diploma in order to pursue UG courses.

It totally depends upon the course you are choosing after class 12th. If you are opting for engineering then there are NITs, IIITs, and government and private engineering colleges which are offering a good course curriculum. If you look for B.Sc, B.Com and BA. then there are colleges for them too.

MH-CET offers admissions both on domicile basis and has some open quota for outstate students. So, if you have a domicile of Maharashtra & do well in the open test then you have a better chance of getting admission in a good college or else you will have to compete in the quota of outstate students.

Yes, you can seek admission in India based on your A level board scores. All boards vis state board, ISC, CBSE, IB, IGSE, etc., are recognised in India for admission in degree colleges. There is a rating mechanism that is followed to convert IB scores to arrive at parity to Indian board scores for allotting merit list for admissions.

In order to get in top IIMS, you have to get more than 98 percentile.

I am unable to understand your question, please rewrite a question.

According to me, you should be choosing science because then you can take admission anywhere in the world if you are good at it, but eventually, you should be choosing whatever interests you.

If you are interested in mathematics then you can go for Bachelors in mathematics, so eventually, it depends only upon your interest.

Yes, you can get your name changed. Just contact the education board you completed your SSC from.

It only depends on which do you want to pursue.