B.Tech

Hi Krishnan,
The better B.Tech course about machines is obviously mechatronics. Robotics also but it focuses mainly on robots only.
So if you want to study about machines, mechatronics is the best one.
But many colleges do not offer mechatronics. So please choose the right one.

You can check by this link:
https://www.resonance.ac.in/reso/news/JEE-Main-Branch-Predictor.aspx

Hello Neha,
As your rank is low, you must try in any other private college or you must try in REAP to get admission in a government college of Rajasthan whose counseling begins from 15th of June.
All The Best

CSE is better as it offers more job opportunities and high pay.

IIT-IIM graduates have edge over other graduates in terms of better companies and higher package because such students are considered the cream of India by large corporations.

IIMs consider only graduation degree marks beside 10th and 12th marks. Your B.Tech score will be considered. Process and weightage of marks differ every year. You may look at IIMs website for details.

Both are good in their own way, you have to select the stream on the basis of your interest.

I'll make it short and crisp. SRM, Ramapuram campus is believed to have better faculty than SRM, Delhi. You can also try for the main campus. For now, Ramapuram is better than Delhi.