CBSE 12th

You can go for any computer career options but you also need to take Maths as a subject for entrance exam.

This is the same question that I too have, according me you do your (UG) in Mechanical engineering (B.Tech) in one of the best colleges in and around India and then, after your degree in (B.Tech), do your (PG) in Robotics and Automation (M.Tech) in India or try to do it abroad countries, and doing Ph.D in Robotics isn't worthy enough and it has no value, if you want to pursue your career in teaching the youu could do your Ph.D in Robotics, otherwise, it's not needed.

There's a very slight possibility of you getting converted to wellingkar, if you perform exceptionally well in GD and PI. Prepare accordingly. All the Best. Thank you.

It depends upon on the college you select. It should be conducted by NCHMCT, and by else.
Thank you.

If I talk about BCA then it's a course regarding programing language like C, C+, etc. and B.Tech has different fields like:
B.Tech in civil engineering
B.Tech in computer Science
B.Tech in Science and engineering
B.Tech in electronics and communication engineering
B.Tech in mechanical engineering

Yes, you can get. By the way, seats wont be given looking at your past schoolings performances.

If you want to study in IIT, then apply for JEE Mains exam. And start preparation for that.

Your profile is good but CMAT score is not too high. You have medium chances.

If you want to become an aerospace engineer. After 12th, from JEE Mains and Advanced and from so many entrance exams, you can get admission in engineering colleges among India than you will surely reach NASA.