So I moved it all to the trash and decided to install fresh from the app store. I go to the app store and get to the Xcode page, where I see the "Free" button. I click that and it turns to "Install ...
You can't run iPhone apps on a Mac computer without an emulator, though that will change with a new set of Macs, coming out by the end of 2020.
I wasn't sure whether to put this here or in the Mac forum, but I think since it is a programming question, it's probably better here? Well, anyhow, here goes. I'm very new to Mac OS and Mac ...