Thanks for reaching out in Apple Support Communities. I understand that your Mac is no longer downloading the photos in iCloud Photo Library that were taken with your iPhone. I also see that other iCloud information such as Notes isn't syncing to your Mac either. I know how important it is to have this information up-to-date on your devices; I'm happy to help. First, check System Preferences > iCloud to be sure your Apple ID is still showing signed in. If so, use the guidance below:
For your iCloud Photo Library I'd suggest using these steps to repair your Library first:
Repair your library when it has problems
If Photos is open, choose Photos > Quit Photos.
Press Option-Command and double-click the Photos icon in the Applications folder (or click the Photos icon in the Dock).
The Repair Library window opens.
Click Repair to rebuild your photo library.
For your Notes I would suggest opening System Preferences > iCloud, from here deselect the Notes checkbox, wait a few moments then re-enable iCloud Notes.
Choose Apple menu > System Preferences, click iCloud, then select the Notes checkbox to turn it on.
Should you continue to have trouble, could you let me know what other data you're not seeing synced from iCloud?
What macOS and iOS versions are you using?