Administrator User

I have had Security Assist build the pages it needs to setup a login system. No Users have been defined yet and when I try to check the display of the userupdate.php it takes me to the login page.

When I check the Pages Manager it shoes that this page is protected (I guess as default) to logged in users.

I want this page to be only accessible by administrative users. I see on the list of available user types in the page Manager that I can set this as Administrator access but I haven't been able to find a reference on setting up a username and password for this type of user.

You can guess that I am very now at this so I'm kind of feeling my way through. If there are any tutorials or information sheets about any of this I'd like to find them so I can read. The getting started PDF gives the idea that multiple levels of users and permisions can be set in place but doesn't give any details of where to access those capabilities.