how should we get into iit's for b arch
In order to take admission in IITs for B.Arch you have to qualify for JEE Main exam to be eligible to appear for JEE Advanced then you have to clear AAT (Architecture Aptitude Test) entrance exam.
After clearing AAT exam you can take admission in IIT Roorkee and IIT Kharagpur for B.Arch course.
Good Luck!!