I followed this and eventually got a massive error message which I think boiled down to problems with the app (I might have got ahead of myself, maybe it wasn't actually ready for me to try), but it did install/open Xcode Previews on the phone, so I think that worked! What I originally meant was that on the canvas, where I select a device in the bottom left, it says I can choose my phone. I thought that would show my preview on my phone. Anyway, thanks a lot, I think I get it a bit better now!

I’m not actually sat at it to check, but I’m pretty sure it’s Xcode 26: it’s a Mac mini that I bought last week (never had one before) so I’ve only just got Xcode, and it should be the latest version