Courtesy of GameDevHQ, they have provided a Pentathlon environment to walk through all of the assets from the DemoScene.

We could grab the XR Origin prefab that came with the XR Interaction Toolkit and have it all set up for us but we want to take a different approach so we can learn how the XR Origin functions.
Let’s begin by right-clicking in the Hierarchy Panel and let’s create an XR Origin.

From here, we need to think of the XR Origin as our Player’s perspective. It decides where our player is in the scene.
Place the XR Origin object to where you want the Player to start.