How can I create an option in the print PDF pop up menu with Automator?

I tried to create a print plug-in for pdf pop-up menu, where I'd like to open the PDF in messages so I can send as a text or iMessage. After a few trials it did launch the messages app but it didn't show the pdf within it, nothing to send. Wanted to try the same plug in with iBooks to see if it works and it did beautifully; saved the pdf to iBooks. I’m using the “open finder items” command. Is there something different I should do to make this work with messages app? My OS is BigSur 11.1. Thanks!