There is no common counselling of NATA. The Universities/colleges and states offering B.Arch programmes will conduct their own separate counselling based on scores obtained in NATA 2019. Once the result is announced by the authorities, the institutes will conduct their separate counselling. You need to check the eligibility criteria of the university/college to which you are applying to participate in the counselling round. You can refer below given article for the further information.

https://engineering.careers360.com/exams/nata

Good Luck!