How to open encrypted file in iCloud Drive

Hi ula115,

If you are referring to the encryption used when you store a file in iCloud Drive, please note the following on the site you posted from:

...many Apple services use end-to-end encryption, which encrypts your information using keys derived from your devices and your device passcode, which only you know. This means that only you can decrypt and access your information, and only on trusted devices where you’re signed in with your Apple ID. No one else, not even Apple, can access your end-to-end encrypted data. End-to-end encryption requires two-factor authentication for your Apple ID and a passcode set on your devices. Some features using end-to-end encryption may require up-to-date software.

Those files can only be accessed by devices signed in your Apple ID, and other decryption methods would not be possible.

If this does not address your concern, please elaborate on what you are attempting to do to increase your chances of obtaining a helpful reply.

Regards.

See the articles Lock a document on Mac - Apple Support

To unlock a document, deselect Locked ( when file is locked , right click on it use get info the box will be shown locked , open finder > before the file small grey lock will be visible ) .

Get file, folder and disk information on Mac – Apple Support