Welcome to the forum.
I doubt that this is the only way, but when I want to open a pdf using Preview (rather than in a container field) I've learned to use the "SendEvent" command for Mac and "Open URL" for PC.
There is additional info here:
and also if the search the forum for "Open Pdf"
Thanks for the reply!
I wasn't certain how to make each record coincide to its own PDF without making a script for each one. However I changed up the wording of my original script and did manage to get it working. For some reason if you clicked out of the container field you could no longer select it(unless you used another script with the goto command) which is why nothing was opening. So I just started my script off by selecting the container and everything seems to be working, although the steps to get there are a little wonky.
Thanks for your help!