HELLO VIKRAM
It solely depend on you. I suggest give as many examples as possible so that you should have options in your hand if you don't get into IIT. Since the topics of all the exam are almost similar but the pattern differs so if you have already studied then why are you wasting your knowledge by just giving any one exams just as many exam as possible so that your chances get increases
you can give exams like SRM, COMED-k etc
https://engineering.careers360.com/exams
HOPE IT HELPS!!