Not sure if this is helpful:
On your Mac, sync all or a selection of music to your iPhone, iPad, or iPod touch.
I recently 'sync-ed' music (selected playlists) from my Mac to and old iPhone (a '4', as I remember) I had not used in years. I connected the iPhone (in airplane mode to make sure it was not receiving, nor transmitting) to the USB connection in my car. It plays perfectly as an 'external device'.
Perhaps 'Windows' has a similar process.