NIT

No, with an 83.5 percentile, getting Computer Science & Engineering (CSE) at any NIT is almost impossible.

CSE cutoffs at even lower-tier NITs typically require 97–99+ percentile, and top-tier ones demand 99.2–99.5 percentile

Yes it is possible infact there are very certain chances with a SC category rank of 9400 in JEE Mains, you have a very good chance of getting a seat in the Computer Science Engineering (CSE) branch in several NITs.

While securing a spot in a top-tier NIT like NIT Tiruchirappalli or NIT Surathkal for CSE might be very competitive, this rank is definitely within the admission range for many of the mid-tier or even some of the older NITs.

Your prospects are excellent and you can confidently participate in the JoSAA and CSAB counselling to secure a seat in a great NIT for CSE.

With a JEE Main percentile of 63.5, your Common Rank List (CRL) rank is likely around 3.2 to 3.4 lakh. At this rank,  getting admission into any NIT is highly unlikely, especially in the open (General) category.

There is not a fix number but several faculty members hold PhDs, including from IITs and NITs, especially in CSE and ECE.

With a rank of 55770 rankand according to the previous trends, you can aim for IIEST Shibpur, NIT AP, NIT Uttarakhand, NIT Srinagar and some other northeastern NITs. You have to sit for CSAB counselling to get these or maybe a better one. Also you can check the details from CSAB official webpage.

You can't get top NITs with this percentile but you can get lower NITs.

Some of the NITs which you can get are :

• NIT Arunachal
• NIT Sikkim
• NIT Manipur
• NIT Nagaland
• NIT Meghalaya

With a 1,27,245 rank in OBC-NCL, getting CSE in any NIT or IIIT is very difficult. CSE seats usually close much earlier. You might get other branches in newer NITs or IIITs. Keep an eye on spot rounds or consider private colleges if you're focused on CSE.

With 91 percentile in JEE Mains there are various good colleges options for you which are mentioned below. You can have chances in Top NITs like NIT Srinagar, NIT Trichy, NIT Agartala which is difficult for you to get Computer Science branch you can make sure your admission to NITs with Computer Science Engineering branch in NIT Patna NIT Durgapur NIT Mizoram NIT Sikkim NIT Raipur. 

With EWS rank of 68741 and CRL rank of 515714 you can not get a IIIT however you can get NITs like NIT Patna NIT Durgapur NIT Mizoram NIT Sikkim NIT Raipur and NIT Goa because they have relatively lower cutoffs than Top NITs like NIT Trichy, Warangal, and NIT Srinagar and NIT Bhopal. You can also look for government funded technical institute like Assam University Pudducherry Technological University.