B.Tech

Above 200 marks are required in JEE Mains for general category and above 150 for Muslim category students.

No doubt, IITs are best followed by Birla, DTU, VIT, NITs.
Check the below links-
https://www.shiksha.com/b-tech/ranking/top-civil-engineering-colleges-in-india/53-2-0-0-0
https://www.shiksha.com/b-tech/ranking/top-mechanical-engineering-colleges-in-india/48-2-0-0-0

RV College is the best. You can also apply for BMS and Ramaiah.

Hello Mukit,
I don't think you should pursue engineering if you have scored only 50%. With only about 60% engineers getting job, it's no good. With many seats not getting filled up, you are bound to get admission. But please think, retrospect and then decide.

Hello Siddharth,
One needs crystal gazing to know future. However, trends indicate that biotechnology is going to have great future. And if you get admission where your aim is, it's the best.

Hello Shyam,
It's not the question of which branch is in demand. Placement is a matter of which Institute also. Recruiters uncannily know which is best college and go there leaving others. As per the report, 40% engineers are not placed. Hence, seek admission in the best college only.

If you pursue integrated course other then IITs, then you will get M.Tech degree also but you will lose chance to do M.Tech from IITs, which will get through GATE after B.Tech.
Otherwise, go to any educational web portal, you will get the list of best private colleges for integrated course.
But lastly

Hello Kishore,
It will be better, but if you pursue integrated course then you will get M.Tech degree also, but you will lose a chance to do M.Tech from IITs, which you will get through GATE after B.Tech. Otherwise, VIT is also a good college to do this course. It is ranked under top 10 by MHRD.*
Last

No, there is not female reservation quota for NIT. but there is state quota seat in NIT.
But, From the year IITs has 20% reserved seat for female. Try to get in IITs.
All the best.