hello aspirant

YES in order to get admission in Naval Architecture in any IIT, you have to give JEE mains and JEE advance exam. But they are considered as one of the toughest entrance exams in india. The alternate options that would be to give other, much easier, entrance exams like IMU CET and AICET. These entrance exams will get you admission in NAval Architecture and are much easier also.  You may not get a direct admission in Naval Architecture.

furthermore, the eligibility criteria for Naval Architecture is as follows :

• Must have passed 10+2 from a recognized educational board with primary subjects of Physics , Chemistry , and Mathematics .

• A minimum of 50% aggregate percentage is mandatory.

Further, to know more about the Naval Architecture course, in detail, you can follow the below mentioned link to know more : https://www.careers360.com/courses/naval-architecture-course

I hope that this will help