Button that adds watermark/header footer to all next pdf pages, with the watermark text comming from dropdown selections

Hey my question is a bit of a mouth full.

Trying to write a java script ( i believe this is the best way) for a button once clicked:

Prints a water mark/ configures the header footer in all pdf pages after the first page. Button is on the first page of the pdf.

The text for this water mark/ header footer, being dependent on 2 dropdown and a text box

E.g

Dropdown box called HSC, options are 1,2,3,4

1 selected

Dropdown box called A/c options are 206,207,208,209,210,211,212,213

211 selected

Text box called reg, with the text "112/18"

When the button is pressed the Watermark/header comes out as

"HSC 1 A/c 211 reg 112/18"

My understanding watermark is the best way to configure this.

Any help will be greatfull.

I am using Adobe Acrobat DC with all tools available.