Hi aspirant,

No there is no need of filing any forms before getting into NIT or IIT.

Admissiins in NIT are done on the basis of marks scored in JEE mains along with the rank and for IIT it depends upon the marks you scored in JEE advanced.

Only you need to fill jee application for getting the opportunity to study in NIT or IIT.

So go for it without any other thought.

Also, prepare very well because the competition is very tough these days.

Hope this answer will help you

Thank you and good luck:)