How do I enter Apple ID verification code?
Sign in with your Apple ID and password on a new device or browser. Look for a sign-in notification on any of your trusted devices. Tap Allow to get your verification code. Enter the verification code on your other device to complete the sign-in process.
Why can’t I type in my Apple verification code?
You do have to quit Settings (swiping up on Settings to get rid of it after double-clicking home button) and then open it again and then enter your Apple ID password and 6-digit verification code one after the other in the password slot.