Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
Hi ge6319,
Thanks for your post in Microsoft Community.
Are you referring to this feature in Word?
In Word for Windows, there is no default support for opening PDF files, as there are other simpler applications like Edge for this purpose, or more specialized third-party PDF viewers. When you attempt to open a PDF file with Word, it will also warn you that this may cause damage to the file.
Therefore, I suggest using Edge to open your PDF files instead. Edge has a simple drawing tool that allows you to markup your documents without converting the PDF file, which would otherwise lead to the loss of your annotations.
I hope the information above is helpful to you, and I look forward to your reply!
Best Regards,
Thomas C - MSFT | Microsoft Community Support Specialist