Your DITA2Go distribution includes a full set of format configuration templates and editable format configuration files, organized in side chains referenced from the general configuration chain; see §39.1.3 Understanding how templates are chained together.
You can override the default format definitions, and define additional formats, in the provided editable format configuration files paired with the templates. Or, you can set up your own configuration template chain for format definitions, and reference that chain from your project configuration file. See §7.2.3 Understanding how DITA2Go builds format chains.
Your project configuration file can reference templates for any or all of the following kinds of formats:
The text-format template is the main template in this collection; it can reference the other templates, but not vice versa. See §39.5.3 Chaining configuration templates.