When you unlock locked notes, the lock icon next to the notes and in the toolbar appears unlocked 
on your Mac, choose Notes > Settings, then click Set Password. If you have multiple accounts, first click the “Locked notes” pop-up menu and choose the account you want to set a password for.
Note: You can also create a password when you lock a note for the first time.
Do one of the following:
Use the login password for your Mac for locked notes: Click Use Login Password. (If your notes are in an iCloud account, you must have two-factor authentication enabled and turn on iCloud Keychain in System Settings to use your login password for locked notes. If you have additional devices, they must be using iOS 16 or macOS Ventura to see notes that are locked using your login password.)
Create a custom password for locked notes: Click Create Password, then enter a password in the Password field. Enter the password again in the Verify field, enter a hint, then click Set Password.
Note: It’s highly recommended that you create a hint.
If your Mac or Magic Keyboard has Touch ID, select Use Touch ID to be able to use your fingerprint to unlock your notes.
See on your Mac, select a locked note.
When prompted, enter the password. (You can also use Touch ID on your Mac or Magic Keyboard if you turned on that option in Notes settings.)
After you enter your password, all locked notes in that account are unlocked, so you can easily view them without entering the password, as long as you’re working in Notes.
Close locked notes
If you want to immediately hide the content of a locked note, you can close your locked notes.
In the Notes app
, choose Remove Lock, then enter the password. (You can also use Touch ID on your Mac or Magic Keyboard if you turned on that option in Notes settings.)If you’ve already entered the password during this session of Notes, you don’t need to enter the password.
If you can’t lock a note
You can’t lock any of the following: