You can use Ultimate Web Builder software with your own previously registered domain name, or buy a new domain name, whether you are hosting with UltimateWB or hosting with another compatible web server.
If you do choose one of the UltimateWB web hosting packages, we can connect your domain name to your web hosting account for you, if you prefer; just provide your domain name account username/password. You can also choose to do it yourself or get help from your domain name registrar, the company where you bought your domain name. It just involves updating your domain name nameservers to the ones we provide to you.
If you are hosting your website with another company, they should help you connect your domain name to them, and will provide you with the associated nameservers for your new web hosting account.
And if you buy both your domain name and web hosting from UltimateWB, we can take care of all the setup for you.