Website Builder comes with Website-building tools that don't require technical skills or coding experience. You can choose from hundreds of themes with placeholder content and images to get started quickly.
If your account was auto-setup, you can skip this step.
Each theme has pluses and minuses, and it may take a couple of days before you know if it fits your needs. While you can change your theme at any time, none of the text and images you've added will be preserved. To avoid starting from scratch if you switch themes, you may want to "test drive" a theme with a minimum of your own text and images until you're sure about it.