want to sync my Mac music library (not apple music) to iCloud

HAC666 wrote:

Thanks... but why.... is it just a move apple makes to force you to subscribe ??

If we're being cynical, yes. iTunes Match and Apple Music (the subscription service) both allow you to offload locally stored files to the cloud from where they can be streamed on demand. While it is potentially possible to sync your music files from one computer to another using iCloud Drive, OneDrive, Dropbox, etc. neither the iTunes not Apple Music libraries are intended to live in such a shared location, and the ways these are updated can interfere with the correct updating of the library. In addition there will be unexpected errors when the library tries to access content that isn't already downloaded to local storage.

What is that you're hoping to achieve by adding your music to iCloud? If you're looking to make a backup this might be better done to an external drive. Consider using Time Machine to avoid bulk copying the entire library each time you make changes, and to cover the rest of your personal data. If you're trying to free up space on your computer for other projects then it is possible to move your entire library out to a separate drive, but that then needs connecting every time you want to use your library. Or you go down the route of iTunes Match or Apple Music, which will let you reclaim the space currently used by your music. Either way I strongly recommend backing up all of that data before you do.

tt2

You can't.

An Apple Music subscription is about streaming music from Apple’s catalogue, not just a syncing service. If you need to to sync your music to other devices see: Sync your device using your computer – Apple Support (AU)

Manual syncing from a computer to an iPod existed long before there ever was iCloud anything.