Import music from a computer to Apple Music on Windows
If you have songs or music video files on your computer, you can import them into Apple Music so they appear in your music library.
In the Apple Music app
on your Windows computer, select the Sidebar Actions button 
at the top of the sidebar, then choose Import.Locate a file or folder, then select Open.
If you add a folder, all the files it contains are added to your library.
Tip: You can also drag a file or folder from File Explorer to the Apple Music window to import it.
By default, Apple Music places a copy of each audio file in the Apple Music folder (Home\Music\Apple Music) and leaves the original file in the current location. For information about adding an alias to the file (instead of creating a copy), see Change where your music files are stored.
When you import an item by dragging it to the Apple Music window or choosing Import, a reference (or “pointer”) to the item — not the item itself — is placed in the Apple Music folder. You might not be able to play the song if you move it.