iCloud notes
You can store notes in iCloud so that you can view and edit them on all your devices as well as iCloud.com. Notes stored in iCloud appear below iCloud in the sidebar of the Notes app. If you don’t see iCloud in the sidebar, you need to sign into iCloud and turn on the Notes feature in iCloud preferences.
Choose Apple menu > System Preferences, click Apple ID , click iCloud (in the sidebar), then select the Notes tick box.
Note: iCloud may not be available in all countries or regions and iCloud features may vary by area.