Before you can use the VR Template, your device will need to be set up for development in Unreal Engine. See the documentation in XR Development for your device to ensure it’s set up correctly.
You generally shouldn’t need any additional setup for the Vive. All that is necessary is to have SteamVR installed, and the OpenXR runtime set to SteamVR (this will usually be done automatically, unless you’ve had other headsets installed on the same computer before).