Вот абзац из мануала по этому поводу:
Figure -
This command creates a dummy figure. Naturally it is unlikely to be useful for any of your final output. However, you might find it useful for representing your characters before they’re built. Plus the Figure object is also included to help you learn IK — choose Structure > Make Editable to convert the Figure
primitive into a full hierarchy complete with anchors and Kinematics tags with angle restrictions. Try changing the various parameters and study the setup of the tags to get a head start with IK.