How to approve my iPhone on iCloud?
[Re-Titled by Moderator]
iPhone 12 Pro Max, iOS 17
Go to your Mac or another iOS device (iPad/iPhone) where your iCloud account is logged in.
Go to Settings.
Click on Apple ID.
Go to Password & Security.
Click on the Get verification code option.
Tap on OK.
Go back to your device which was asking for the approval and you should see the tab asking for approval is gone and you iPhone approved.
- based on https://www.digitalcare.org/how-to-approve-iphone/