IIT Indore - Indian Institute of Technology

You have to score a 35% marks to get a rank. For iit indore, if you scored 43% then you will get admission in it.

Hello
IIT indore take admission through JEE advance. Its do not take admission through JEE mains.

Yes, you can. If you can clear GATE, then you will be called for a separate written test in the institute you have applied to. If you clear that written, you will be called for a personal interview.
There are many good courses in IISC and IITs. Please check the webpage of the Mathematics department in their respective websites.

Hi Aditya, you must achieve excellent grades and look for companies offering internship positions to international students. It will be difficult, until and unless your college in India has some sort of tie-ups with any organization in Germany. You can think of looking for a job after completing your internship in India as an alternative. Hope it helps.