A family of Microsoft presentation graphics products that offer tools for creating presentations and adding graphic effects like multimedia objects and special effects with text.
Thanks for providing the additional info (although it's best to exclude or at least mask the email address since this is a public forum accessible to the bad guys as well as the good ones).
Since Big Sur & Office are fully updated, when did you last restart the Mac?... That would be the next consideration.
Do you have any keyboard helpers or utilities that provide keyboard control? As a troubleshooting step start the Mac in Safe Mode then launch the program to see if you have the same result.
If the issue persists in Safe Mode, restart normally, then create a new Standard User Account to see whether the the behavior occurs when logged in as that user.
Please provide detailed descriptions of all results.