Sounds like you have read an article on the PC Version.
If you are using the latest non-beta Version which 15.23.2, there are to ways to convert(export) to PDF.
- The first is Go to Save As Menu and choose PDF.
- The second is new just added a Ribbon Button, with an Acrobat Document icon.
The first method uses Apple's PDF Conversion Routine convert from PPTX to pdf.
The new method evidently Microsoft and Adobe have come up with a new system.
- Locate on Ribbon The Acrobat Icon

- Click on button you will switch to this window:

- Do as annotation says.
- Your Presentation will become a PDF.
Apparent the Mac version does not add Notes. But If you have either Acrobat, Acrobat subscription, or PDFpen Pro ($99.00 approx.) you can add the notes manually.
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NOTE: Neither I nor Microsoft has any vested interest, in this product. I, or MS (so far as I know),own no stockin the company that author's these utilities/applications. I purchased a copy for my own use and find it helpful and for me, it has not done any harm to my system. As with all software, including software from Microsoft, there is always the slight, possibility of buggy or harmful behavior, but this has not happened so far for me.
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