MyBB Community Forums

Is it possible to have a forum which consists of 2 or 3 subforums only?

In other words, the forum has subforums but doesn't allow any posts to be made in itself, they can only be made in the subforums.

There's a plugin for this, but it has a bug and messes up your forum, so i wouldn't install it, i think the author may know about it, not sure.

If you set their parent to be a category, yes. Either that or just change the permissions of the parent.