I need to set new computer so when I right click and Copy on a PDF file from Windows Explorer that it pastes the content of the PDF file as an embedded document automatically when pasted into Word 365 Pro Plus.

This does work without additional software. I have verified it on multiple computers and it is working the way I described on my existing computers running the same version of Office. I open my letterhead and paste the PDF file itself without ever going into Acrobat and the file is automatically embedded.

There is also no need to go to Insert Object or to use Paste Special from the Home ribbon which create additional prompts I don't get on these other computers when doing a copy and paste into Word.

On the new computer the default behavior is to create and icon for the PDF file and shows no file content.