Pages not displaying..

Hello,

I’ve just started using WordPress and am trying to get to grips with it.
I seem to have a problem with pages not displaying.
When I create a page in write -> write page I enter the title & page contents and click on save.
The page now shows in manage -> pages.
I have created an about page this way and it shows on the site (https://www.802.eu.com) but when I click on the link on the page I get an 404 error.
I am obviously missing something but can;t figure out what…
Can someone help me out?

E.