The "Collaborative Task List" is one of the standard process templates that appears in the New... menu. It gives you a head start for how to organize your process workflow as a collaborative checklist. The use of round bullets for each task and subtask means the work can be done in any order. If you need step-by-step processes, simply change the list type to numbered "Step-by-Step".
You can do several things here.
Assign the existing groups to users:
Clicking on "Person 1". Click on "Assign".
Fill in the text for the tasks:
Click to the right of the bullets and simply type in the task information.
Add more tasks:
Go to the end of a task. Press <ENTER>, as though you were adding another item to a bullet list in an email message.
Add more members to the task list:
Go to the end of the last task. Press <ENTER> to create a new task.
Then press <SHIFT><TAB> or the "outdent" button "to outdent" the task.
Then type "Tasks for @Bruno" (replace Bruno with your 3td team member's name). Then add subtasks by pressing <ENTER> and <SHIFT>.