Insert Fillable PDF form data into a collection (visa-versa)?

Our HR department creates PDF’s. Travel vouchers, leave…etc… How would I take the data from the filled in PDF and put them into a meteor collection.

I’m guessing the best way would be server side generation?
User logins - > Generates the PDF hr created (I have no control over the form creation) -> The PDF is filled in with basic user info. > User fills in the rest of the info. -> All of the user input gets saved to a collection, and this data could be reproduced back into a PDF.

My head is spinning trying to figure out XDF data and how PDF fill works.

Any advice, or help? I don’t have that much PDF knowledge. Thank you.

Well, can’t say a thing on XDF in this very case yet I think it might well be implemented with some tool like that https://ds11.pdffiller.com I get it that you want to create one on your own but I guess it would be some way more convenient, but it will cost your company some