You will want to use a recovery contact, or a recovery key. If that is not available, neither will be the info in iCloud.
See: Use Advanced Data Protection for your iCloud data - Apple Support
WARNING: If you use Advanced Data Protection, you’re responsible for your data recovery. Because Apple won’t have the keys required to recover your data, you’ll need to have a Recovery Contact or Recovery Key set up on your account. You can use these additional recovery methods to regain access to your data if you ever forget your password or lose access to your account.