Hello Ritesh, you wont be able to pursue Astrophysics directly from the undergraduate level.

But since Astrophysics is your primary goal, you can attain it by a number of ways.

1. A degree in Electrical and Electronics Engineering, Electronics and Telecommunications or a course in Engineering Physics would be a great way to go. Then you can go for Masters degree and Ph.D. in Astrophysics.

IITs, BITS Pilani (any campus) or other prominent institutes are good options for engineering. Engineering Physics is a course offered by only a few IITs. Further, universities like the Massachusetts Institute of Technology, Stanford, UC Berkeley are excellent for post graduation. For an Indian Institute, then IUCAA, Pune is a good option as well.

2. You might go for general line i.e BSc. or BS-MS in Physics and then finish your Ph.D. in Astrophysics. IISc, IISERs and IITs like IIT Kanpur are really good institutes for a degree in Physics.

At IISER Mohali, you can have Astrophysics related courses as electives from the second year. More courses follow in subsequent years. Also, if you are interested in Space Technology, do find out more about IIST, Thiruvananthapuram.

All the best for your future!