There are plenty of seminaries in the US, even more now to fill the need of those who don’t go to E”Y. I’m a bit out of date on them, but you can see the adds in the frum nagazines/newspapers. The need for dorms will depend on whether the student body is local or not, and whether the community can board students or not. But I don’t think that a dorm makes a seminary.
But I guess this is what Alizgit means that “going to seminary” means different things to different people- ZD, to you it means moving away from home to a school with a dorm.