EU VAT extra field and Business details into Invoice pdf

Hi,
Let me explain what i need, when you select the purpose in the confirm invoice step and choose business option, it shows two extra fields (Business name and VAT no.). Here i would need a third field for extra information ¿Is possible add a extra field here?.

And my last question is ¿how can i add the above fields data (business name, vat no and third field) into the pdf invoice?

I mean something like this:

Bill to:
Business name
VAT no.
Address (Third field)

Thanks for your help.