Hello emmaturner07,
Welcome to Apple Support Communities. We understand that you would like to clear some of your Music storage on Mac without deleting songs from your library.
To delete items from your computer but not from Apple Music, you can find and remove downloaded songs. Hover over the song with your mouse, then click the More option that appears. You can see which songs are downloaded by looking for the download icon. Check out Delete music, movies, and TV shows from your device.
If you have made changes that do not seem to be reflected in storage, empty the trash as well.
Take care.