Do the following in Unity:
- Go to Edit > Project Settings.
- Click on Player in the left-hand menu.
- Scroll down to Other Settings > Configuration.
- Check that the Active Input Handling dropdown is set to Both.
Then do the following:
- Delete your MainCamera gameobject from your scene.
- In your Assets folder, navigate to StarterAssets > FirstPersonController > Prefabs.
- Drag the PlayerCapsule prefab into your scene and expand it to show the child GameObjects.
- Drag the MainCamera prefab into your scene and make it a child of the PlayerCapsule.
- Drag the PlayerFollowCamera into your scene and make it a child of the PlayerCameraRoot.
The rest should either work the same way or it is (hopefully) self-explanatory.
Let me how if this helped or if you got stuck somewhere. 