macOS Mojave 10.14
Subscribe to a playlist in iTunes on Mac
When you join Apple Music, you can subscribe to playlists created by any Apple Music contributor. When the owner updates the playlist, it’s updated in your library.
In the iTunes app
on your Mac, choose Music from the pop-up menu at the top left, then click Browse.
Click Playlists and find a playlist you want to subscribe to.
Control-click the playlist, then choose Add to Library.
To view your subscribed playlists, choose Music from the pop-up menu at the top left, then select a playlist in the sidebar on the left, below Apple Music Playlists.