This is a sample page. It is different from a blog post because it will stay in the same place and appear in your site navigation (in most themes). Most people start with an "About" page that introduces them to site visitors. It might look something like this:
Hello ! I'm a mechanic who aspires to be an actor, and this is my website. I live in Bordeaux, have a great dog named Russell, and love vodka (as well as being surprised by sudden rain during long walks on the beach at sunset).
...or something like that:
123 Machin Truc was founded in 1971, and has been providing the public with quality contraption ever since. Located in Saint-Remy-en-Bouzemont-Saint-Genest-et-Isson, 123 Machin Truc employs 2,000 people, and manufactures all kinds of cool stuff for the Bouzemont community.
As a new user of WordPress, you should go to your dashboard to delete this page and create new pages for your content. Have fun!