How to turn off Two-step verification?

According to Apple:

Make sure that you're still signed in to iCloud on each of your devices. You might be asked for your Apple ID password.

1. Sign in to appleid.apple.com.
2. In the Sign-In and Security section, click Account Security.
3. Click Turn Off two-step verification. Click again to confirm.
4. Create new security questions and verify your date of birth.

You'll get an email confirming that two-step verification for your Apple ID is off.

How to turn off Two-step verification?

You can't, if it has been more than 2 weeks since you set this up.