It’s easy to conflate these two, but they solve different problems - one you already have, the other you opt into.
Your booking page
Every account gets a public booking page at <your-business>.rexabook.com from the moment you sign up, with your services, availability, and profile details on it. This is where a customer actually books, and it exists whether or not you ever touch the site builder.
The website builder
The site builder is an optional way to add more pages around that booking page - a proper homepage, a services page with more detail than the booking flow shows, a gallery, a story page. It’s not a replacement for your booking page; it’s additional pages that link to it.
When you’d want more pages
If your booking page alone covers everything a customer needs - what you offer and when they can come in - you may never need the site builder. It’s worth reaching for when you want to tell a fuller story than a service list allows: showcase work with before-and-after photos, answer common questions before they’re asked, or just make a stronger first impression than a bare booking form gives.
Getting started
See Building extra pages with the site builder for how a page actually gets made, and Rich content blocks for what you can put on it.