Add a website to your wiki by copying this HTML code

<iframe src="http://address.ofinternet.site"
frameborder="1" scrolling="auto" width="100%" height="600"></iframe>

Click on the Embed Widget embedwidgeticon.png

Click Other HTML.

embed_widget.png

Replace the 'address.ofinternet.site' with the internet address of the site that will be displayed on your wiki page. You can change the dimensions by adding different numbers in the width and height. Click Save and Save again.