This shortcut gets a random wallpaper matching the resolution of the iPhone 13 Pro from Unsplash, and then sets it to both your home screen and lock screen.

The wallpapers there are quite nice, and in combination with running the shortcut daily via an automation you will always wake up to a fresh, beautiful wallpaper!

If you are using a different iPhone, you can edit the resolution used in the shortcut's steps. In the future I might automate this.