which are the best colleges give admission in b arch based on jee mains paper2 score.

The colleges in order are:

Indian Institute of TechnologyRoorkee
Indian Institute of TechnologyKharagpur
Maulana Azad National Institute of TechnologyBhopal
National Institute of TechnologyCalicut
National Institute of TechnologyHamirpur
Malaviya National Institute of TechnologyJaipur
Visvesvaraya National Institute of TechnologyNagpur
National Institute of TechnologyPatna
National Institute of TechnologyRaipur
National Institute of TechnologyRourkela
National Institute of TechnologyTiruchirappalli
BITS , MesraRanchi
School of Planning & ArchitectureBhopal
School of Planning & ArchitectureNew Delhi
Shri Mata Vaishno Devi University Jammu & Kashmir
School of Planning & Architecture Vijayawada
Chandigarh college of ArchitectureChandigarh
SRM UniversityChennai
Punjab Technical UniversityPatna
PM College of EngineeringSonepat
Himgiri Zee UniversityDehradun
Gitam Institute of TechnologyVishakapatnam
Deenbandhu Chottu Ram UniversitySonepat
Dehradun Institute of TechnologyDehradun
ICL Institute of ArchitectureAmbala
Faculty of Technology and EngineeringVadodra
MGMs Jawaharlal Nehru Engg. CollegeAurangabad

Almost all the NITs if you have a decent rank.

SPAs, and some NITs give admission on the basis of JEE MAIN paper 2. But you need to get a very good rank