B.Tech Astronomy

The course for Astrophysics
Obtain a bachelor's degree in astrophysics.
You will need to take calculus-based physics, computer science, and astronomy. A few electrical engineering classes may also be required. Bachelor's degree programs typically take 4 years to complete.
10 Astronomy Institutes in India that are fostering Space.
Aryabhatta Research Institute of Observational Sciences, Nainital.
Indian Institute of Astrophysics, Bangalore.
Indian Institute of Science Education and Research.
Indian Institute of Space Science and Technology, Thiruvananthapuram.
Inter-University Centre for Astronomy and Astrophysics, (Pune)

Dear Gaurav!
In B.Sc & M.Sc, our more focus will be on the Research and Development wheares in B.Tech & M.Tech, your role will be doing engineering behind the work. It's you who decide which one is suitable for you. After B.Tech and M.Tech in Aerospace Engineering, you will work as a Engineer. But after B.Sc. M.Sc. (recommended Ph.D. you will the scientist for research. I would recommend you to go for B.Sc. And then go for abroad for Masters. In India, the scope in Space Science is not as that much as in foreign. Hope this helps. Upvote the answer if you feel satisfied. Ask any query at anytime.
Good Luck.