Generally, the iframe tag is used to embed whole websites. The only way is to create an html page that pulls content from two websites and displays them side-by-side. A frameset is one way of doing this.
But due to some reason “Website will not allow Firefox to display the page if another site has embedded it”
https://support.mozilla.org/en-US/kb/xframe-neterror-page?as=u&utm_source=inproduct
Two or Multiple websites on one page
HTML example using iframe to try display 3 website into a singple web page.
<html>
<body>
<iframe
width="300"
height="300"
src="https://www.wikipedia.org">
</iframe>
<iframe
width="300"
height="300"
src="https://www.google.com">
</iframe>
<iframe
width="300"
height="300"
src="https://www.youtube.com">
</iframe>
</body>
</html>Output:
Note: But nowadays Google, Facebook, and other lots of websites do not allow you to load their website or webpage on your Webpage for some security issues.
Do comment if you have any doubts and suggestion on this HTML code.
Note: The All HTML Examples codes are tested on the Firefox browser and the Chrome browser.
OS: Windows 10
Code: HTML 5 Version