Are you able to advise how to add columns to the contact form? and also to edit the height?
I am trying to avoid having to use another plugin for this.
Did you actually mean you want to add the new fields to the contact form? If so, you can do it via Contact Form > Edit the contact form, then you can add the new field on this page. The DGWork contact form is based on Contact Form 7 plugin, here is the documentation: https://contactform7.com/docs/