Hello.

Fill your choices, wait for results of the 1st round, go to nearest nit/iit depending on the seat u r alloted in 1st round whether its nit/iit. Do necessary documemt verification and all. Chosse either float if u want to participate in further rounds, freeze if u want to lock ur choices amd slide if u want only the branch upgradation.

If u choose float, wait for next or further rounds results. U have to go to the alloted college if you want to freeze ur choice.

The overall steps are

Registration, choice filling

Choice locking

Seat allotment

Document verification,physical reporting at reporting centers

Choosing float,freeze,slide

Final admission at alloted institutes

In detail info about the above steps please go through this webpage

https://engineering.careers360.com/articles/josaa-counselling/amp