Astronomer

As you are a 11 th class commerce student, Yes you can become an astronaut or study astronomy. It's not very late as you are in 11th only. So to get into the field of astronomy, you are adviced to change your subject in 12th only so that you do not face any problem in pursuing Bachelor's in astronomy. After that you can complete Masters in feilds like MSc Astronomy etc. So yes, you still have chances of becoming an astronaut. 

Yes, you can pursue an M.Sc. in Astronomy after completing a B.Tech in Aerospace Engineering. Many institutions, such as IIT Indore and IIST Trivandrum, accept B.Tech graduates for their M.Sc. programs in Astronomy and Astrophysics.Admission Requirements:IIT Indore: Requires a Bachelor's degree in any engineering field or a B.Sc. in Physics/Mathematics.IIST Trivandrum: Accepts B.Tech graduates with relevant experience in Astronomy and related fields.Ensure to check specific entrance exam requirements, such as JAM or GATE, for admission.

A degree in aerospace engineering or aeronautical engineering will be an advantage for Indian Astronauts. Students must have essential knowledge of Science (PCM and geology. Nasa hires engineers with a master's degree or a doctorate in aeronautical engineering or a related field, and minimum of 5-10 years of experience in aerospace field. 

No, sorry jimlee but this is not possible.

Yes, you can as you have basic knowledge of Science.

After high school, students must study undergraduate and graduate Aeronautical Engineering courses, Astrophysics courses, or any other courses that are pertinent to the field in order to become astronauts. Other excellent programmes include B.Tech in Space Technology, B.Tech in Aeronautical Engineering, M.Tech in Aeronautical Engineering, etc. Following that, you would need to enrol in research programmes like a Ph.D. in aviation, astronomy, or aerospace or aeronautical engineering.

You can become astronaut by joining iisc. People go to space either as an engineer if it is very important to send engineer in space. You don't gi to space because you studied astrophysics. Iisc or any other Institute can't make you astronaut. But if you love space. Study astrophysics in iisc, Aries, iist, iucaa. You need to give exams like GATE and JEST. Than they will take interview. You will join as Ph.D. or integrated Ph.D. student or M.Tech student. You will study space by staying on earth with top most instruments.

Hello,
No, in India Astronauts are from IAF. You need to join IAF in the flying pilot branch to become a pilot. Best wishes to you.

Hello Rohith, aah, it's very nice to hear from you that you want to become an astronaut. Unfortunately no country accepts nationals from any other country to become astronauts. In India, only pilots of IAF have been allowed to become astronauts. You have to take your pick. Best wishes to you.