How add a "for Office Use only" Section

I would like to create a form that has a “for Office use only” section. That can be filled out by someone is the office after the customer has completed there part of the form (post submit I guess. . I  would prefer that the customer not see the office section. Thanks

That's possible when you show fields only on edit mode.

Here's a guide for that: https://www.jotform.com/help/389-How-to-Show-or-Hide-Fields-on-Edit-URL

So after the user submits the form, you can let someone in your office update the user's submission by providing them the edit URL.

To do that, just create another email notification, add the edit link on the email message and set the email recipient to someone in your office.

If you need further assistance, let us know.