Thanks for submitting a question about themes. While the theme controls the style of a page, managing post and page items in the back end is something that falls within conventional WordPress site development.
For example, managing speakers for a conference can be accomplished in many different ways, but most commonly this would involve creating a custom post type, so you can add new speakers as post items, edit, and publish them to be displayed on a single page or multiple items appearing in an index (like blog posts).
BoldGrid alone is not equipped to handle all of that functionality. There are plugins that can aid you in creating custom posts types, but this would be an ideal case for contacting a WordPress developer. The link in the previous paragraph shows how you can use a popular plugin to create the custom post types and how to create the page templates that will display them. For the latter part we’d recommend creating a BoldGrid child theme.