For phone numbers, you can create a URL hyperlink using the tel: protocol.
See https://stackoverflow.com/questions/1009181/url-scheme-for-phone-call
I definitely agree with the desire for a form filling feature. So far I've needed it rarely enough that I can use https://www.sejda.com/pdf-forms to add fillable fields after the fact, but I have some things I've done with Adobe InDesign that are too complex to use that post-processing strategy every time. I *REALLY* wish Affinity Publisher made form filling fields possible.
