how do i move music to icloud?

Turn on Sync Library with Apple Music - Apple Support

"If you subscribe to Apple Music*, you can turn on Sync Library to access your music library and music that you've downloaded from Apple Music on all of your devices."

*I think Apple also still offers Match which also does what you want, and at a lower price, but they are heavily pushing people to use Apple Music instead and Match is almost never mentioned in their documentation anymore except here:

Subscribe to iTunes Match - Apple Support