I'd be surprised if anywhere let you in with little/no background in theory and no instrument. People have argued on this post that it's about willingness to learn etc, but you need to foundations there to begin with, they won't just let anyone in who's willing to learn.
I think it's more important to have a certain level of experience in composition, and a foundation in music theory. In this case, institutes will often disregard whether you play an instrument or not.