Hello  Aspirant,

Congrats for getting good percentile. This year total 869010 students attempted jee. You can calculate your approximate rank using formula :(100-percentile)*869010/100. That is 43,450 will be your approximate rank.

The chances of you getting seat is easy. It is difficult to say the obc ncl rank. You can predict the colleges you will get using below link:

For last year cut offs of nit:

https://www.google.com/url?sa=t&source=web&rct=j&url=https://engineering.careers360.com/articles/nits-cutoff-for-top-btech-branches/amp&ved=2ahUKEwickbTG99_nAhW7zDgGHXgwCwQQFjALegQIBxAB&usg=AOvVaw2OXl9cMS4B7GJ9DfTIJZCg&ampcf=1

Hope this is useful.