Get started designing a public website with your custom domain
A public website is included with the Office 365 Small Business plan. (Be aware that Office 365 Small Business plan is no longer available for purchase, and for other Office 365 plans, the steps for learning about and working with an Office 365 public website are different than those shown here.) After the website is set up the way you want it to look, you can change the website address to use your domain, like www.fourthcoffee.com. You can customize the site by choosing a template, adding your own text and logo, and so on.
To get started working with your public website in Office 365 Small Business:
Sign in to Office 365 with your work or school account.
Choose Public Website.
The steps in the Public Website wizard show you how to get to the design tools in SharePoint Online to customize your website. Then, you can change the URL to use your custom domain.
Note If you’ve been using Office 365 for a while, you might have two public websites with the service. You can keep and use both sites and share them publicly. However, you can associate your custom domain with only one of these sites at a time.