About iCloud Data Recovery Service
iCloud secures your data by storing it in an encrypted format. If you forget your password or device passcode, iCloud Data Recovery Service can help you decrypt your data so you can regain access.
When you store your data with iCloud, one of the ways Apple keeps your data private and secure is to store it in an encrypted format. iCloud Data Recovery Service decrypts your data on your behalf whenever you need it. Some examples include regaining access to your data after forgetting your password, or signing in to access your data on iCloud.com. With iCloud Data Recovery Service, as long as you can successfully sign in, you can access your photos, notes, documents, device backups, and more.
For certain sensitive information, such as your Keychain, Screen Time, and Health data, Apple uses end-to-end encryption. This data is not accessible via the iCloud Data Recovery Service. Only you can access this information, and only on devices where you're signed in to iCloud. Your device passcodes, which only you know, are required to decrypt and access it.
To make sure you can recover all of your data, you can also set up an account recovery contact or use a recovery key. Either of these methods will give you an additional way to recover your data including information that's end-to-end encrypted.