One can join BArch with the help of NATA and JEE Mains paper-2 into many top colleges.

To be eligible for participation in NATA 2019 counselling, candidates have to score the minimum cutoff marks in the two individual components and also in aggregate.

All the colleges under NATA conduct separate counselling sessions.To be eligible for counselling conducted by these institutes, one needs to qualify NATA 2019.

You cannot get admission into NITs and SPAs through NATA but you can get admission in those using your JEE MAINS paper-2 score and rank.

You can write AAT(Architecture Aptitude Test) to get into IITs based on the eligibility criteria and qualifying marks.

For more information go through careers360.com 

Best of luck!!