Recovery Key for old iphone

I am not given that option in "edit" security. I have these options"

Password

Change Password

Trusted Phone Numbers

Add trusted phone number

App-specific passwords

Generate password

Two-Factor Authentication

On

I should have provided more detail in my first post. This is for an iPhone 3s. Running iOS 6.1.6 (The software is as up to date as it can be)

I finally got it out of the "loop" of asking for the recovery key. I just kept hitting cancel, like ten times! I got it to work enough for its purpose. And currently can use it as an old iPod for an old Bose Sound Touch.

I was just having a heck of a tie getting it to get out of the loop of asking for the recovery key.

In a related question, shouldn't I be able to generate a recovery key? Or is that no longer an option for me since I have two-factor authorization? Sorry if this isn't the appropriate response. And please advise if I should post this question separately.

Thank you.

Thank you. If I temporarily stopped 2FA, could I generate a recovery key for future use for my iPhone 3s?

Once I have the recovery key, I would go back and turn on 2FA for my newer devices.