Themes
Themes are a way of changing the look and feel of a website. The theme for this website (Beautiful Jekyll) is different than the 2 example websites (which use ) you can see in the navigation bar at the top of the page.
Many more themes are available. I usually look on jekyllthemes.io/free for themes (Jekyll being the system around which I create websites), but not all of the themes on there may fit what you are trying to do. Some for example, all revolve around posts (post as in semi-regular mini-updates, like a blog), which is great if that’s what you want to do, but probably less useful for most people who want a website for their business or hobby.
If you prefer, a paid for theme is also possible, but I’d recommend start with looking at the free ones first.