What should I prepare for selection in Joint Astronomy programme?

Hello Sir, I am currently in last year of  B-Tech course in computer science branch. I always want to be in astrophysics field. Because of different field I do not have much knowledge in physics so should I do Honours in Physics so to get selected in interview of Joint Astronomy programme ? And should I give JEST or JAP or do anything else so to get into astrophysics universities?

@DEEVIJA You should register in their website at IISC for Joint Astronomy Program: http://admissions.iisc.ernet.in/web/NewUserRegistration.aspx

Students wishing to apply for this Programme should indicate Astronomy and Astrophysics as one of their department preferences when filling up the application form for Research Programmes.

You need to qualify at least one of the following national level entrance exam -

1. JEST
2. GATE (Phy)
3. CSIR-UGC JRF
4. INSPIRE Fellow (DST INSPIRE Scheme)

Here is the list of all the eligible exams: http://www.iisc.ac.in/admissions/

Once you qualify any one of these exams and fall within the required cut off you will be called for an interview (JAP interviews are separate from IISc Physics interview). The interview is mainly to check your basic knowledge of physics.

Also do read this important information: https://www.crazyengineers.com/threads/want-addmission-in-astronomy-or-astrophysics-field-after-doing-be-or-me-in-eee.46987/#127110