How to show notification message as popup on webpages

I am using Concrete5 version 8.5.9 and PHP version 7.4 .
I want to figure out how to display a notification message on my webpages.
The notification message popup shows on the top right corner of my webpages as a alert message and it’s closed with a push button of close.
This notification alert popup also contains a "Click Here" button containing an URL link.

Thanks

Javascript is the approach webdevs use, combined with CSS and HTML of course.

Check out this tutorial:

There are many others out there, the above is only one example.

For example;

https://www.w3schools.com/w3css/w3css_modal.asp