There are a total of 477 colleges who provide admission in B.Arch based on NATA score. But COA doesn't conduct counselling of NATA and hence the candidate have to apply to the desired Institute among the participant Institute on the basis of your NATA marks. To be eligible you have to score minimum cutoff marks in individual components and also in aggregate.   Every Institute have their own counselling norms for NATA counselling  thus tou have to meet eligibility criteria specific to a Institute as well.