How do I verify my key gen

This information should help.

Set up iCloud Keychain for each device that you want to add. When you turn on iCloud Keychain on an additional device, your other devices that use iCloud Keychain receive a notification requesting approval for the additional device. After you approve the additional device, your iCloud Keychain automatically begins updating on that device. With two-factor authentication, you can turn on iCloud Keychain without approval from another device.