Basically you have two separate applications you need to configure respectively:
- The TVHeadend Server that you installed from the APP Store (or that you installed somewhere in your Network). You can check Section 6 of this thread [Obsolete] Instructions for Viewing Live TV
- The TVHeadend (Client) PVR Addon in Kodi. This would need to be configured with the IP Address, Port, User and Password of your TVHeadend Server.