I got 82 marks in nata and 9 78 cgpa 8n class 12
You did good!
Well in order to get admission in Architectural college you need to score in either of the 2 exams.
Firstly, you can give the JEE paer 2 and
Secondly the NATA Exam ,
To clear the cutoff for NATA you need to score atleast 80 out of 200 as for the general category .Since,you have cleared the cutoff so there are chances you might get a good college
All the best!