Simply by using WordPress standard method:
Thank you, Matthias for screen capture, it saved me some time changing one website language to english 😉
If you want to change the icon dispayed by Google in mobile search, you can read this good post from James.
WordPress > Appearance > Customizer
If you don't see that menu item, switch your theme from "Twenty Twenty-Two" to "Twenty Twenty-One", or even better, install "theme "Intentionally Blank".
Please note: with Oxygen installed, the activate button in the themes screen looks disabled, but it's working fine.