This tutorial walks you through the basics of creating standard posts in WordPress. Be sure to view the following tutorials on the Post Editor and Categories vs Tags to understand how to plan your structure and get the most from the editor screen.
Your Obox theme comes with several custom styles and elements you can access by clicking on the Obox button in the post or page editor. Unlike shortcodes, these options apply special styling directly to your content, which can be previewed in the editor. For best results, write your post content first, then go back, place your cursor where you want a styled element to appear, then select an option from the Obox menu to insert the element for editing. Detailed instructions for using Obox Styles are available in the Obox Styles article in your Theme Documentation.
For a detailed overview of using posts and custom post types in your theme, structuring categories and using the Obox Post Options panel, refer to your Theme Documentation.