Hello Akshay,
To get admission into B. Arch / B. Planning in NITs/IITs, you'll have to secure a good rank in JEE Mains Paper-2/ AAT. You can go through the following link for last year's cutoffs for B. Arch/B. Planning programmes in NITs/ IITs:
https://engineering.careers360.com/articles/jee-main-cutoff-for-b-arch-b-planning
For more details about AAT, visit:
https://engineering.careers360.com/articles/jee-advanced-aat
Best Wishes!
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