I‘d like to suggest using Wordpress. It is easy to setup and pleanty of informations, plugins, themes and tutorials are available online.
Nitrado has a YouTube tutorial on how to setup Wordpress with your webspace and domain:
Unfortunately, it is in German but maybe you can follow the steps shown in the video.
About your domain: It sounds like the domain is already registered but needs to be linked to your webspace - The video above also shows how to do that.
Let me know when you still have problems setting things up.