The URJ will soon be creating our own tutorials and videos on WordPress specific to RJ Web Builder 3.0. In the meantime, if you would like to start learning, please review some of the available resources below.
Themify Builder: The most powerful and easy to use page designer and builder for WordPress
WordPress.org: Documentation
OSTraining: Free beginners classes
WPBeginner: A beginner's guide
Lynda.com: WP essential training
WordPress for Beginners