Making a YouTube video from powerpoint presentation file with embedded audio file
https://support.microsoft.com/en-us/office/turn-your-presentation-into-a-video-c140551f-cb37-4818-b5d4-3e30815c3e83

On the File menu, select Save to ensure all your recent work has
been saved in PowerPoint presentation format (.pptx).
Click File &gt;
Export &gt; Create a Video. (Or, on the Recording tab of the ribbon,
click Export to Video.)
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