After you review your website and get it looking just the way you want, you're ready to publish it. (There's no option to "unpublish a website" once you publish it, though you can change and republish the site any time.)
Note: If you're using a Business, or Business Plus plan, once your site is published, any data transmitted from it will be encrypted using a SSL (Secure Sockets Layer) certificate. This works only for managed domains, not third-party (external) domains. Find out how to Upgrade my plan.