This page explains how to use a countdown widget to be integrated in a layout like this:

Use this example and change some parameters:
Change these parameters:
| Parameter | Description |
|---|---|
| title | Text in the page |
| date | date for countdown calculation |
Go in a folder of your Appspace library where you want to store the widget.
Click on ADD and Other:

Select Web page:

Select Website link and paste the link in the URL field:

Type a title and a caption like an click on Save.
You can use the widget in a layout.