Turn off two factor verification authentication

Read the document: "Two-factor authentication for Apple ID" - Two-factor authentication for Apple ID - Apple Support

Two-factor authentication is enabled by default on new Apple IDs and cannot be turned off.

"If you're already using two-factor authentication with your Apple ID, you can't turn it off."

If you have an account where you only very recently activated Two Factor Authentication, note this section of the Apple support article -->

"If you updated to two-factor authentication inadvertently, you can turn it off within two weeks of enrollment. If you do, your account is less secure and you can't use features that require a higher level of security."

Note that if you did indeed recently turn it on then you should check your email. If you don't see one, look in your junk folder.