Editing a pdf in adobe

[Guest]

How do I edit an existing pdf document to include numbers that correlate with text in and drop down box, and give me a sum (total) at the end of the document?

[try67]

You can add fields to the file and then use the built-in calculation action of a text field to sum the other fields.

There's plenty of information about how to do that in the Acrobat Help section, as well as here: https://acrobatusers.com/tutorials/