I don’t know to change the wallpaper of the watch

I’ve used it for 2 whiles, but I can’t know how to change the bottom of the watch.

I went to the settings and in the screensaver I didn’t see the option, I tried holding down on the screensaver too but without success.

Maybe I’m missing something or there’s a separate app and I haven’t seen it. But I’m unable to change the background😅