vim :hardcopy equivalent

[me . groff]

Hi list,

after years of doing my administrative letters with vim :hardcopy plus some 
settings[1], I'd like to move on to groffing them with identical look and be 
indepenent of the editor.

So, typewriter look, significant whitespace, page number/total heading.

Being new to groff and a bit lost in macro packages as well as the docs - how 
would I do that, or where has such been documented before?

Greetings,
Marcus

[1]: https://mro.name/2022/brief-dina4.txt