If you have cPanel hosting, you can upload a website that was built with pretty much any type of software. The one you mention has been discontinued and therefore is no longer supported (you are on X5, the latest version was X8 so you even have an older copy). So it may be wise to not be dependent on that application moving forward.
If you are primarily reliant on software building your site, then GoCentral may be a smart choice until you can learn the basics of building a site on your own.
Any web builder, such as GoCentral, is platform based and you do not have access to the code. Templates are what they are, features and functionality is what it is.
Take advantage of the 30 day free trial to see if GoCentral meets your needs. If you find it to be too restrictive, then take a look at WordPress.