Hello, and thanks for your question!
You can then test a website on your account with us directly on our server using either the temporary URL, or by modifying your hosts file to force your computer to resolve your domain to our server.
If you already have a website built, then you can simply migrate all of your files over to your hosting account on our server. Or you can start from scratch and work with the temporary URL version of your domain until you are ready to point it to our name servers.
Please let us know if you had any other questions at all and we'd be glad to help!
- Jacob