attempting to sync all devices without sucess

"Sync-ing" non music data like contacts, passwords, files, on your devices is a bad way to think about this process.

it is much easier to 'get your head around it' when you call it Sharing -- 'making that data available on your iCloud Account', then Sharing it back to each of your devices that uses the same Apple-ID.

The essence is that the Master copy is kept on iCloud.

Andrea....I have the following comments:

• Are you trying to sync music content across your devices, or something else? Please let us know what you're trying to sync.
• Can you provide the MacOS version on your MacBook Pro? (Click on the Apple menu-->About This Mac).
• Can you provide the iOS and iPadOS versions on your iPhone and iPad? (Settings--->General-->About)
• Note that in recent years, the iTunes app on Apple devices has "morphed" into the Music app on these devices. You may not find iTunes, but most likely will find the Music app.
• And lastly...make sure all your devices are logged into the same AppleID account.

Can you give a little more info on what you are using and what problems you have encountered. For example iTunes is needed for some transfers but finder is used more recently.