If you change your theme, your content will remain. Changing the theme only changes the look and style of your site. Follow this video tutorial to install iThemes Builder Air:
Make sure you create the custom child theme and delete all the layouts except for the default layout. This will make things simpler as you are building your site.
This video takes you through all of the Builder settings in detail:
Learn how to edit your default layout.
This tutorial is part of a series of e-courses created by Cat Scholz to empower you with using the self-hosted version of WordPress to achieve your internet marketing goals. Get more information and/or sign up: