M.Tech

Both the fields are same, but B.Tech in IT will provide you better career options. So, you can opt for B.Tech in IT.

Manipal University, IISC-Bangalore and PES University are some of the known institutes.
Check the below-mentioned link:
https://engineering.shiksha.com/me-mtech-in-karnataka-categorypage-2-59-1-0-0-1-106-2-0-none-1-0

You can look for jobs in public sector. You can try to look for openings in various public sectors like:
1. CONCOR.
2. ONGC.
3. SAIL.
4. HPCL.
5. ISRO.
6. BEL.
There are many engineering colleges, who needs M.Tech students as an assistant professor. You can opt for those opportunities and prepare for PSU jobs.

Aerospace is a good branch. You are already a technical student, so I suggest you to go with M.Tech and if you have interest in marketing, banking and accounting then you may go for MBA. But, as per my choice M.Tech in aerospace is better for you.

Yes, you are eligible for M.Sc in cyber security or information security. University of Madras offers this course. Instead of M.Sc there is M.Tech in cyber security. You can consider IIIT, Hyderabad too.

The best one is IIT, Hyderabad.

You can refer to the official website link:
http://www.aiet.in/AdmissionProcedure.html

It is possible in Maharashtra because the Maharashtra government provide evening course.

Hello,
Yes, you can pursue an undergraduate degree in one branch of engineering, and then do a Masters in another branch.
I hope it helps. If you have any further questions, kindly revert

Start preparing for GATE. You need to keep your basic concepts clear. You can refer Made Easy notes or study materials from Career Launcher. Keep practising through test series conducted by various coaching institutes.