Hi ISHITA ,

You have to first apply for the josaa counselling,then if you get selected in any of the round in any college then you to first visit your nearest NIT,IIIT,IIT or any other GFTI for physical reporting.In oder to know more about the process please visit the link given below:-

https://engineering.careers360.com/articles/jee-main-counselling-seat-allotment

Hope this helps you.

Best of luck.