Can't find a SMTP account wizard for my verification code

There are actually two options that you can use to add a sender email. 

Option 1: You can add your email address as a sender using the verification code. Here's a guide that you can follow: https://www.jotform.com/help/238-How-to-Add-a-Custom-Sender-Address-to-an-Email-Alert. Please note that the emails will still be sent from our mail servers.

Option 2: If you have your SMTP details, then you use those and set your sender address. Here's a guide that you can follow: https://www.jotform.com/help/244-How-to-Setup-SMTP-for-a-Form. On this method, the notification will be sent to your own mail server because of the SMTP details you have.

To edit or delete your sender emails, you can follow this guide: http://www.jotform.com/help/241-How-to-Edit-Delete-the-SMTP-Emails. In your case, you should be able to add the verification code directly in the email wizard where you added the sender email in the first place.

I hope that helps.