he finds out about Shamballa where he learns the art of the magic from the ancient one. The character of the movie is very important and he plays a key role in the Infinity war movie.
While Hawkeye certainly isn't the most powerful of The Avengers, there's a case to be made that he is the most important. (Exhibit 1: The result of his absence inInfinity War.) InEndgame,Hawkeye will almost certainly serve a critical role, but thedetails of that roleremain to be seen...