This starts an assistant, the first step of which you can skip. In the next dialog, enter the address of the website. You must enter this with the prefix "http".
Click on Add and then on Next. If the page should always be updated automatically, leave the default settings and then click on Next.
The last dialog is used to define how large the website should be displayed.
In conclusion, all you have to do is
indicate where the web page is displayed on the slide.