You can use Oculus API and OpenXR api (which are selected in vorpx tray menu), personally it feels like OpenXR runs better with quest 2 than oculus api.
If oculus is only vr you have ever installed it will be default openxr application anyway so you just need to select it in vorpx, if not once you run oculus app on pc it will ask you to set openxr by default or like suggested find this setting in oculus app settings.
You dont have to download anything additionally.