hello rbabu,

your chance of getting seat in NITs is very less.

If your rank is in top 500 then you can easily get an architecture seat in top NITs. like SPA Delhi,NIT Trichy

The cutoff for B.Arch courses is about 50% of the total marks.

Above 70% and you can get a seat in one of the finest institutions in India offering B.Arch.

For B.Arch at IITs the admission is based on JEE Advanced Rank and for admission in NITs, SPA, BIT Mesra, SMVDU the admission is based on JEE Main Paper 2 Rank.

The Opening rank for SPA New Delhi was 98 and it closed at 798. For candidates that did not have any state quota the closing rank was 827 in NIT Tiruchirappalli and 2377 in NIT Patna.

you can check here all detail about cut off-

https://engineering.careers360.com/articles/jee-main-cutoff-for-b-arch-b-planning

hope this would be helpful.

Good Luck.