build setting: switch to target platform
install AR foundation + ARCore XR from Unity registry in Package Manager
build setting > Player setting:
OpenGL before vulkan
min api : android api level 26 (store 30)
scripting backend: ILL2CPP
uncheck armv7 and check arm64
xr plug-in, check ARCore
create XR > AR session + AR session origin
ar session origin > add component > ar plane manager
outliner > create XR > AR Default Plane, put it prefab
drag that plane prefab into AR Plane Manager (plane prefab)
direction mode: horizontal
ar session origin > add component > ar raycast manager
ar session origin > add component > AR environment prob manager
(extra) Direction Light > add component > HDRLightEstimation.cs (put ar camera there)
(extra) ar session origin > add component > PlaceOnPlane.cs (place holderPrefab there, above raycast manager there)