If you navigate to HelpCrunch Knowledge Base → Settings, you'll see there are several sections in its right menu. Let's start with General settings.
This is where you can change your knowledge base's name and header text (the one that will appear on your knowledge base main page). Don't forget to specify the language of your knowledge base.
General settings also contain the field for specifying a custom domain for your knowledge base. Your default domain at the beginning is crunch.help, but you can change it any time your want. You can read more on how to set up your custom domain in this article.