iCloud Security Code Recovery

This is not something that I've encountered, but you you can see this:

Get a verification code and sign in with two-factor authentication - Apple Support

The last part says:

If you still can't sign in

If you can’t sign in, reset your password, or receive verification codes, you can request account recovery to regain access to your account. Account recovery might take a few days or longer, depending on the specific account information you can provide to verify your identity.

Of course, you could just create a new Apple ID with a new email address and, as you say, start from scratch.

ardoksm wrote: ..Yeah, this is what support told me as well.

The issue is that this is NOT verification code, nor two-factor authentication. This is a whole separate thing called "iCloud Security Code".

I can sign in absolutely just fine on app and browser.

I saw that. Again, I have no experience with this-- I'm just looking around and making guesses like you.

Here is something that I found:

If you can’t access another device that uses your iCloud Keychain:

• Go to Apple menu > System Preferences
• Select iCloud, then Keychain, and enter your Apple ID info if prompted.
• Click Use Code, then choose Forgot Code
• Click Reset Keychain to replace your keychain in iCloud, then Reset iCloud Keychain to confirm. Follow the onscreen steps to create a new code

That was from an old MacWorld article.

Again, your best bet may be to create a new Apple ID with a new email address, and start from scratch.