Overlay Video Playback means that upon clicking your video content, it will open in an overlay so you can view its content immediately, instead of opening it in a new tab or browser.
Follow the steps below on how to use overlay video playback in your site.
Add a Grid Tile in your Section.
Click Add Tile and select:
Media from Library - if the PDF file had already been uploaded in the Media Library
Upload media - if the PDF file still needs to be uploaded.
You can type in a Caption or an Alt Text on the left navigation pane if you wish to.
Click the Action tab, select the button beside Expand & Play Video. You can uncheck the box to Allow download, if you don't want the video to be downloaded from your site.
Click Publish and click View Site to see how it looks like in your site.