Typically for that you have "headless server" - a server that has no display connected, and to which you access though other means (a web browser, an app, ...)

Typically for that you have "headless server" - a server that has no display connected, and to which you access though other means (a web browser, an app, ...) → this is Jellyfin & Co. Then you have "servers with a display", a desktop or workstation → Kodi. Kodi does not have a client, nor a client-server architecture. All of these applications are primarily servers.