Playing music in Plex via Sonos & Plex Cloud

I’m new to plex and am clearly not the smartest person when it comes to this stuff so excuse my ignorance here. With that being said, I just uploaded my entire music library from my computer to Plex but noticed that when I turn my computer off I can’t play songs via the Plex App through my Sonos system. I assume this is because I need to use Plex Cloud? I have a premium subscription but cant figure out how to now get all the music I just uploaded into Plex Cloud.

Again, the goal here is to be able to play music on my Sonos system without having to turn on my computer. Any help/suggestions would be appreciated.