I need help to do the following:
Send #1 pdf document.
Recipient before opening #1pdf document receives pop-up or notice that in order to open the document they must click “agree”/”yes”.
When Recipient clicks “Agree”, #2 pdf is autofilled with Recipients previously entered name, current date, signature.
Recipient opens #1pdf file. Sender receives #2pdf file signed.
Hello! 
I’ve tried my best to answer, but I’m not 100% sure what you’re trying to do. Some more info on the use case would be super helpful, if possible...
Send #1 pdf document.
Recipient before opening #1pdf document receives pop-up or notice that in order to open the document they must click “agree”/”yes”.
I don't think Zapier is the best place to handle logic like this. I think you'd want to ensure your pdf software was handling this at their end
If you've got your heart set on using Zapier for this, I'd recommend creating a flow which interrupts the path to view the document:
Send email asking for confirmation
Client confirms
Triggers sending of pdf to view
Recipient clicks “Agree”, #2 pdf is autofilled with Recipients previously entered name, current date, signature.
Again, this would need to be something that's handled by the pdf software
You would need a front-end flow to support a lot of this, and there are so many PDF options available to you, I would honestly recommend ensuring you've exhausted their capabilities before trying to do this in Zapier.
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