Hi,
Does it have to be via HEOS?
I would avoid using a computer (PC) as a source to stream from. Just adds complication. A NAS is a better approach. Or local media, as in an external 1TB drive or something like that (or even flash drive) with the music on there in whatever container you prefer (MP3, FLAC, etc) and just access it that way. A basic NAS on the network (wifi) would be fine, always on, always accessible. Can rip the CD's on the PC or whatever she's using and transfer the files to the NAS on the network and then HEOS would access the NAS as a source for the music files.
Ripping CD's is pretty easy with Exact Audio Copy (EAC). It's free. It will label the albums and songs and get album art. Just plop in a CD and start the process and it will do the work. All you have to do is take out the CD and put in the next one. Very easy, not hard to follow the GUI. Lots of options to customize or just let it do it auto with a Wizard after questions for super simple setup.
I do this with a NAS server and Plex for my server and streaming platform. This way a Roku or any other device, can access my Plex server and see the music with album art and everything and stream that way from my server.
Very best,