You can create an action that will create entities in Autotask there are a number of different types of Autotask Entities you can create. Depending on which you choose to create the parameters you need to supply will change.
Start by selecting Autotask Direct API: API: Create an object from the Perform this action dropdown.
Next, select the type of entity you would like to create from the Autotask Entity Type to Create dropdown. Then you can start selecting the fields from the Fields... dropdown and setting their values.
You must make sure that you select all the fields that include an asterisk (*) in the field name, these fields are mandatory in order for the entity to be created in Autotask.
As with the order actions, you can set a boolean expression in the action settings to only create the entity in certain circumstances.