Mail Merge from specific worksheet with custom VBA popup Script?

[Ndev777]

Hi guys and gals,

Unfortunately for me, I am Excel and Word technically challenged

I humbly seek the wisdom of you amazing people... I am trying to help a friend who is an accountant and like me, also has no clue in achieving this mail merge feature..

Trying to accomplish:
A word document that would fill mail merge the respective fields, but it would work from either one, several, or all worksheets available.

In the Excel screenshot examples below, I've listed two worksheets business's by their "Code", BBB and FPP, which represents the business's (Bob's Burgers and Frankies Pizza)

In the Word screenshot below, you can see that I have the written and inserted the fields I want populate.

What I'd like to have, upon opening the Word document that is linked to that excel file, is a popup box (VBA script?) which asks... Type in Code(s), seperated by a comma to mail merge, or a "All Codes" mail merge.

I've included a photoshop "Mock-up" screesnot to give an example...

Is this do-able? Thank you all who reply in advance

Warm regards,
Val

screen-1 — ImgBB
screen-2 — ImgBB


word — ImgBB
word-popup-mockup — ImgBB