B.Tech

Hello,
RV College is better than PEC college as
It has a very good student life due to advantage of location (Bangalore). The same also allows for a lot of exposure to the IT sector. It has good quality faculty and infrastructure along with prime location in he center of the city. It is a good place

Hello Ujjwal
As JEE mains results are announced, so many college started their admission processes but after the releasing of class 12th marks, it goes on the peak point. So, be aware about your college.

Admission in NITs for engineering degrees is based on JEE Mains score. If you are targeting IITs then you have to additionally appear for JEE Advanced if your score is above cut off in JEE Mains.

I am providing a link of a college predictor. Try it.
https://www.shiksha.com/b-tech/resources/jee-mains-college-predictor

Kalinga University does not offer CS seats at this rank but you can try for the same.

You can check here by this link:
https://www.shiksha.com/b-tech/resources/jee-mains-college-predictor

BITS, Hyderabad is the best option for you.

You won't get admission in IITs until and unless you qualify JEE Advanced.

Yes, all these courses have good opportunities. All these are still niche sectors in India and in all these sectors you have opportunities to get into PSUs. Chemical will be easier among the 3 and opportunities in mining, power generation, research and development.