Use the OVRControllerPrefab prefab in Packages/Meta XR Core SDK/Prefabs.
When adding the prefab to each controller, set the Controller property of the OVR Controller Helper script to L Touch for the left controller and R Touch for the right controller.
The controllers need the OVRManager script at Packages/Meta XR Core SDK/Scripts to work. You can add it to the OpenXR Player.
Setting the "Controller" property on the right controller prefab.
Adding the "OVRManager" script to the OpenXR Player prefab.