Default page is a blank, basic page you should use to build any page you wish. You can either use TinyMCE WordPress editor or Visual Composer plugin that came with the theme.
With Visual Composer you can build anything you want. You can use our pre-loaded templates or Visual Composer pre-loaded templates.
You can learn more about Visual Composer here https://wpbakery.atlassian.net/wiki/display/VC/Visual+Composer+Pagebuilder+for+WordPress