This is an example page. It is different from posts because it always stays in the same place and (for most themes) is displayed in the navigation bar. Most people start with an "About Us" page with an introduction for potential visitors to the site. It could say, for example:
Hello! during the day I work as a bike courier, at night I am an aspiring actor and this is my blog. I live in Berlin, have a big dog named Jack, like the Fantastischen Vier and a cold beer.
As a new WordPress user, you should use the Dashboard to delete this page and create a new page with your own content instead. Have fun!