First, I agree with Graham that this could be suited for a userform if it will be used in an environment that allows use of macros.

To insert an AutoText field named firmmail, you can type "AutoText firmmail" without the quotation marks, select what you just typed, press Ctrl+F9 and then F9. Before you press the F9 key it will look like { AutoText firmmail }. After you press F9 it will display whatever the entry holds. Note, you cannot simply type the braces {}; you must use the Ctrl+F9 to insert them as a pair.

You must create/save the AutoText entry first. Again, which tool will work best depends very much on what it is you are trying to do.

The same method can be used to display document variables or custom document properties. Instead you would be using { DocVariable firmmail } or { DocProperty firmmail } fields instead. "Firmmail" is the name of custom document property or document variable that you created.

Unlike AutoText, document properties and/or variables in a template become embedded in a document created from the template. Graham and Greg Maxey worked together to create a tool which makes it easy to insert either. CC⁄V⁄BM & DP Tools Add-in That is not part of the interface, you have to download it and use it. It is the simplest way I know to insert document variables without programming.