To access the ui/Theme-Builder, you can navigate to it in the Admin menu >> Components >> ui/Theme BuilderPro.

In this interface you can manage your pages:

This tutorial provides a quick introduction to setting up the Joomla content management system and the Warp framework. It covers the basics of configuring and using the Warp framework to create a functional website.

How to Install ui/Theme-Builder Package

The ui/Theme-Builder Package comes with the ui/Theme-Builder Pro component, smart search plugin, content plugin, module and uithemebuilder template.
Follow these steps to install ui/Theme-Builder Package