One domain one server no need extra user

I have a deep question. I had installed CWP. My VPS isn't for selling hosting. It's for an e-commerce website. So I don't need any users. I want to manage my website from VPS whether no user is required or needed because the VPS is only for one website.

So how should I maintain this,
1. if I connect my domain in the root control panel. Can I manage a website without a user?
2. If I create a user under my domain name but the domain not added in the root control panel, so what will be the nameserver address?

without User account the domain will not work.

So what would be the nameserver name in root panel?

http://wiki.centos-webpanel.com/how-to-setup-name-servers

http://wiki.centos-webpanel.com/how-to-setup-name-servers

if I add nameserver "ns1.example.com" and "ns2.example.com" in the control panel then where the "example.com" should be added? Control panel or User Account?