How to make a video from PowerPoint presentation?
Click the File tab and choose Export. (In earlier versions, use Save
& Send or Publish.) Choose Create a Video. You have some choices for
quality and what to include, but the defaults are usually good.
Click Create Video and wait until it’s done.
another simple method is-Save your finished PowerPoint by clicking "File" then "Save As" and naming the file. Play your PowerPoint video on your computer or connect your computer to a projector so you can show it on a big screen.