A webpage is part of a website. It is in the form of text and images. Web pages are connected by links. Clicking on a link makes another webpage appear. Webpages are hosted on web servers and downloaded and viewed with a web browser. Web pages are sent to the browser in HTML code. The writer of the page can write HTML directly, or use a computer program to convert other writing to HTML.
For example, each Wikipedia article, like this one, is a page of the large Wikipedia web site.