Share disk is a macOS Recovery feature that allows you to share the internal storage of your Mac with Apple silicon as an external drive with another Mac. This feature is useful for transferring files between two Macs, or for troubleshooting issues with your Mac with Apple silicon. Share disk is only available on Mac computers with Apple silicon, and it requires a Thunderbolt or USB cable to connect the two Macs. To use Share disk, you need to start up your Mac with Apple silicon in macOS Recovery, then choose Utilities > Share Disk. On the other Mac, you can access the shared disk from the Finder or Disk Utility. References: = Use macOS Recovery on a Mac with Apple silicon, How to access macOS Recovery on Apple Silicon M1 Mac, Apple Silicon Macs to Feature New Boot and Recovery Interface, New Mac ..., How to Enter Recovery Mode on a Mac with Apple Silicon

In the Notes app, you can lock notes to protect your sensitive information. You can access your locked notes using your device passcode or a custom password. If you have multiple Notes accounts, you choose the locking method for each account (for example, your iCloud account). You can also use Face ID or Touch ID to access your locked notes, if you enable this option in the settings. To lock notes with a custom password, you need to go to Settings > Notes > Password, choose an account, and tap Use Custom Password. To lock notes with Face ID, you need to go to Settings > Notes > Password, choose an account, and turn on Face ID.
To lock or unlock a note, you need to tap the More button and then tap the Lock icon. You can also lock orunlock all notes in the Notes app by tapping the Lock icon in the bottom toolbar. References: Lock your notes on iPhone - Apple Support, How to Lock Your Secrets in the Notes App (and Why You Should) - Lifehacker