ADP is created upon initialization of the HA pair. There’s nothing to really configure in the GUI.
it will partition disks out to either root-data or root-data-data configurations. RD is typical on FAS and RDD is typically on AFF. The root is much smaller than the data parts. You can actually look up on huw.NetApp.com and see sizes based on your model and drive count.
you can run “storage disk show -partition-ownership”
and it will show the partitions and which controller owns them.