Presentations are not linear documents. This means that each page has elements (texts, forms, etc…) that will not automatically extend to the next page, as it happens in a Word document. That’s why you’ll probably use this format when you want a one-page resume and prefer to edit or deliver them in PowerPoint.
To edit presentations you can use MS-PowerPoint (MS-Office) or Impress (LibreOffice).
Hint: if you use PPTX, because for Powerpoint file format, you cannot display multiple CVs in the same document (one per page), so you would have to choose OpenDocument Presentation instead