AR game sample

I haven't tried it myself, but the demo project on this repository for Godot ARCore might work: https://github.com/GodotVR/godot_arcore

As far as I can tell, AR and VR does not come in Godot by default. There are some generic classes to enable the support, but they rely on proprietary plugins, which you must add separately (and they are in various stages of development). Though I haven't tried them, my research seems to indicate that they are not production ready yet and may have issues. But you can take a look at the plugins here and see if they work well enough for your purposes. https://github.com/GodotVR