If you have a .txt or .m3u file saved on your device, most players like the IPEXO IPTV Player allow you to import it directly from your local storage. Important Considerations M3U8 Xtream Playlist - GitHub

A popular player for Android, iOS, and Smart TVs. To set it up, choose "Login with Xtream Codes API" and enter your server URL, username, and password.

Open the app, go to Media > Open Network Stream , and paste your M3U URL.

Specifically for Android TV boxes, this app allows you to add playlists by entering either an M3U URL or Xtream Codes.