The PDF Viewer widget is a useful feature to show the PDF files that are hosted on your own domain.
Source: use the media library to select the source of PDF uploaded to media or use the URL if the PDF file exists on your domain at a different path.
Navigation Controls: set this true to show a navigation button through which users can navigate between PDF pages. You can set the text for your previous and next buttons.
Zoom Controls: You can enable or disable the zoom controls for the PDF.
Style
On the style tab, you can customize the PDF alignment, controls alignment, spacing between controls and the PDF, space between zoom and navigation controls and some border styling.
You can also customize the navigation and controls on the style tab, to make it inline with your branding colors and style.