It depends on the size of the HTML page and how you want to display it. The easiest way is to create a screenshot and paste the resulting JPEG / PNG file into the presentation. Due to the reduced size, small details will not be recognizable to the audience, and, of course, you will not be able to interact with the html page. So there are two alternatives:
prepare images (screenshots) or enlarged parts of screenshots and insert into the presentation;
to demonstrate a “live” page, temporarily leave an impression and a presentation presentation and use a browser .
The decision depends on the main issue of the presentation: if it is only the presence of a website or its overall design, then this is alternative number 1; if it is functionality / usability / general use of a website / web application, this is alternative # 2. Of course, you can combine both.