Click on the PDF field that you want to connect to a webform field.
At the bottom of the Field options panel, when asked
How would you like to fill this PDF field? select
From a connected webform field.
Choose which webform field you would like to fill this field with. You can search or scroll.
For some fields, such as names, you can make additional output format selections.
Click the grey + sign on the page you want to add the new webform field.
Select the PDF field where you want the data to output.