IIT

Dear aspirant, Glad to meet you. Considering previous cut off it is difficult to get seat in CSE in any NIT and even IIITs and GFTIs. Your rank must be below 20000 to get seat in a NIT in CSE. Do not loose hope, you may get seat in any other branch if you are interested. Even Its hard to get CSE in any of NIT on 95 percentile. For general category you will have to score 99 percentile if you want CSE in NIT but these are tentative reports and they can vary for this year.
99 percentile means the General Rank would be around 8690. The OBC rank with respect to the CRL rank is around 1500- 2000. It is a great performance indeed. You may get chance in top NITs such as NIT Warangal, NIT Surathkal, NIT Rourkela and many other top NITs.

Dear aspirant, Basically the difference between different IITs and any other college (any stream) is their approach. Students at IIT are exposed to more different practical approach than others and hence the learnings are more efficient and effective and different from others. Second factor is the quality of faculty. Faculty members teaching at different IIT are top notch and have different teaching skills or method and this makes a huge difference. Apart from all this, students are also taught some extra subjects in different IITs which also make huge difference. In such highly competitive environment, students take that extra bit because of the resources available to them and this is what makes them stand out from others.

Dear aspirant, Glad to meet you. To get admission into nits you don't need your JEE Advanced marks, you just need to score very well in JEE Mains. Coming to nits to get computer Science in best nits you need to score more than 230 in JEE Mains. If you want admission in iits and to choose CSE branch you need to score rank of less than 200 to get into top 5 iits and less than 600 to get into top 8 iits. IIT :
In open category, to get CSE in top 5 IIT, your rank should be under 250. Rank under 700 gives CSE branch in all AVERAGE IITs
Rank under 100 gives CSE in IIT Delhi
And rank under 60 gives the BEST THING POSSIBLE in India : CSE Branch In IIT BOMBAY. You need atleast 2.5 to 4.5 thousand rank to get in the worst iits (but even the worst IIT are better than best private college and many nits, gfti). NIT:
To get CSE in NITs your rank should not exceed 5,000.