B.Sc Physics

You should opt for aerophysics course.

You must appear for NEET UG, then if the student qualify, then you will be studying MBBS for 4 and a half years, then 1 year internship and then must appear for NEET PG, then if he/she is among the toppers then you can get radiology.

If you are not strong in mathematics, then don't think about physics because physics always use calculation.

Ramnarain Ruia College and University Branch of MU is best to pursue B.Sc physics.

First, decide the university from which you want to study and country were you can go. You should be ready with your passport and visa. You can check the previous record of that institutions.

Yes, you have the physics background, and for aerospace, physics is recommended. Score well in IELTS and GRE exam, and draft a good SOP.

Hello Adwaith,
That depends on your ability to grasp things.
S.Chand publishing books authored by Brijlal and Subramaniam is a very simple book and anyone can understand. If you are looking for advanced or in detail of a particular topic, I would recommend you to refer foreign author books.
1) Sears and Salinger, Thermodynamics, Kinetic Theory and Statistical Thermodynamics.
2) C Kittel and H Kromer - Thermal physics.
3) Advanced engineering mathematics - Erwin Kreyzig 5th Edition, Wiley Eastern Ltd.
4) RPFeynman, RBLeighton and M Sands - The Feynman Lectures on Physics, Volumes 1 & 1, Narosa Publishing House, 1998.
All the best.

For civilian ATC controller, you need M.Sc or B.Tech.
For more information, you can visit the below mentioned link:
http://www.atcguild.com/jobrqrmnt.asp
To become ATC controller in IAF (or a Fighter controller), you have to write AFCAT exam with B.Sc or B.Tech and join admin branch initially and then try for ATC / FC.
You can refer to the below mentioned links:
http://careerairforce.nic.in/
& http://www.nausena-bharti.nic.in/

You have to calculate your PCM marks only, but some colleges include English also. So, I would advice you to go through college's website in which you want to get admission.