Hello dear

Congratulations on this great score!! You did well.

Based upon your rank, I checked the previous year's JoSAA cutoff for roung 7 and here are the possible options for you- 
IIT Indore Metullurgical Engineering and Materials Science 
IIT Kharagpur Ocean Engineering and Naval Architecture
IIT Gandhinagar Materials Science and Engineering
IIT Patna Mechanical Engineering
ISM Dhanbad Engineering Physics
IIT(BHU) Metullurgical Engineering

Thus, according to me, you should go with Indore if you don't have any branch preference due to many obvious reasons like city, proximity, also the environment here is great( I am currently pursuing my B.Tech from here, so have an experience). Even non CSE students are great at coding, thus we definitely have a well developed coding culture. Academic wise, it is at par with the older IITs( you can check the statistics from the official website of IIT Indore). And having IIM in the same city gives us the advantage of having more cultural fests and competitions. This was completely my opinion, you could search about them more if you feel like. The other options which I have listed are good as well ( the same explanation as of Indore goes for Gandhinagar). 
Thus, choose wisely according to your preferences. Look at the insights of the various branches and choose the one which interests you. You may also refer to the college predictor link - https://engineering.careers360.com/articles/jee-advanced-college-predictor

I hope this helps. All the best!!