can't edit my two-factor authentication

2 Factor Authentication uses a verification code to verify your identity instead of security questions.

From the article below.

Do I still need to remember any security questions?

No. With two-factor authentication, you don't need to remember any security questions. We verify your identity exclusively using your password and verification codes sent to your trusted devices and phone numbers. When you enroll in two-factor authentication, we keep your old security questions on file for two weeks in case you need to return your account to its previous security settings. After that, they're deleted.

Two-factor authentication for Apple ID - Apple Support

If you have 2 Factor Authentication enabled, there aren't any security questions. What questions are you trying to change?

You are welcome.

Two-factor authentication for Apple ID - https://support.apple.com/HT204915

"Can I turn off two-factor authentication after I’ve turned it on?

If you already use two-factor authentication, you can no longer turn it off. Certain features in the latest versions of iOS and macOS require this extra level of security, which is designed to protect your information. If you recently updated your account, you can unenroll for [within] two weeks. Just open your enrollment confirmation email and click the link to return to your previous security settings. Keep in mind, this makes your account less secure and means that you can't use features that require higher security."