If you are referring to the device continuing to play a list of videos over and over, restarting when it reaches the end of the list, that is completely dependent on the player. There's nothing that can be done from Serviio's side to force a player to restart the list.
I can't say if LG has such functionality within their built-in player. It may require an external player that has such functionality. Roku players do have that ability within their Roku Media Player app, and it's possible that your LG might be able to install VLC video player, and it might permit a playback loop. Any Android-based player (such as the Nvidia Shield) would depend on the app used for playback. I did just check VLC, and it can be set to play continuously either a single video or all videos in a list (such as a playlist displayed by Serviio). I'll put a link to a site that explains the settings at the bottom of the page.
I would expect that most (but perhaps not all) apps have some form of playback looping, but I'm unfamiliar with any that might do so. But there should be no problem using Serviio as the media source for most apps.
https://www.techwalla.com/articles/how- ... ntinuously