Hello,

Admission in to IIT for B.E/B.Tech is based on merit in JEE Advanced and the seats are filled through JoSAA counselling. Joint Seat Allocation Authority (JoSAA)  is responsible for conducting the counselling for admission in to NITs, IIITs, GFTIs and IITs. Candidates qualifying in JEE Main will be eligible to get seat in NITs, IIITs, GFTIs and the candidates qualifying in JEE Advanced are eligible to get seat in IITs. You need not to apply for each IIT separately. The counselling for admission in to all IITs is done through single window that is JoSAA. As of not the official schedule for JoSAA counselling is not yet announced. Once the schedule is announced you can register for the counselling up on qualifying in JEE Advanced. The registration for JoSAA counselling 2021 may start after JEE Advanced results declaration. Until then you have to wait and keep an eye on updates. To check the news related to JoSAA counselling 2021 and important dates you can use the link below

https://engineering.careers360.com/articles/josaa