Place the laptop behind/below the TV, hook it up via HDMI, install whatever software you want on it (I use plain linux and VLC, but you can install Jellyfin and use the web interface if you want to), use a bluetooth keyboard/mouse combo to control it. You can enable USB wakeup if you want to minimize power usage, but you have to make sure the keyboard is plugged into a USB port that's powered when shutdown then (if that's even possible given your config).