Hi Internet Know How,
Thank you for your questions as I am happy to help!
Can you please clarify if you are attempting to copy an Ad group in the UI or Microsoft Ads Editor?
The link you are referring to is a help link for Microsoft Ads Editor, and if you are experiencing a technical issue, I would like for our engineers to review your system. Please check your private message so we may start the verification process.
At this time, we are unable to copy and paste ad groups on the Microsoft Ads UI Platform, which is why you are not able to locate this feature.
I hope you found this information helpful, please let me know if you have any additional questions as we are always happy to help!
Thank you for choosing Microsoft Advertising!
Sincerely,