Hi.
If you already have iTunes installed when you first install Apple Music it will import the existing iTunes library to Apple Music, and use the same media folder, typically C:\Users\<User>\Music\iTunes\iTunes Media. If iTunes wasn't installed then it would normally use C:\Users\<User>\Music\Apple Music\Media. Within the media folder there are normally separate subfolders for each type of media; music, podcasts, TV shows, movies, etc., followed by subfolders for artists/shows, etc. Apple Music for Windows works the same way, even though it essentially only manages music. Content from the Apple Music service, that contains DRM, and is only valid while you have an ongoing subscription, is placed in <Media Folder>\Apple Music in another set of artist subfolders. You cannot change this behaviour. Moving files by hand breaks the link to the library.
You can potentially change the layout of the library slightly, that is whether or not a /Music subfolder is generated, by editing the hidden .plist file in the media folder, changing the layout value from 1 to 0, then turning the Keep organized... option off and back on again. That said if you really want fine grained control over your library you would be better off reverting to iTunes by uninstalling each of the newer apps. Unlike Apple Music, iTunes has a scripting interface which allows you to perform complex updates to batches of tracks that would be difficult/tedious to do by hand. This can include scripts that will move and rename tracks to your preferred location and layout such as https://samsoft.org.uk/iTunes/scripts.asp#CustomRenamer.
tt2
