Hello there

The minimum eligibility for BSc in Astrophysics is 10+2 in the science stream with compulsory subjects like Maths and Physics . If you have studied physics and maths in your 12th, then you are eligible for the course. so, yes you are eligible to pursue career in B.sc in astrophysics in IISER

For more further informatrion check the link given below

https://www.careers360.com/courses/astrophysics-course#:~:text=Eligibility%20Criteria%20(UG%20%26%20PG)%20of%20Astrophysics&text=Candidates%20must%20possess%20a%20Higher,subjects%20in%20their%20class%2012.

Thanks