A Phase can be further broken down into multiple work categories. A Work Category is needed when entering time to describe the work performed. They can also be used for budget tracking and scheduling work plans.
Click the three-dot on the Phase that you want to add the Work Categories to.
Click Add Schedule Item > Add Work Category
Work Categories can only be added to Phases when the Phase Time Tracking setting is configured to "Track Time By Work Category."Select the standard Work Categories to add from the list.
Click Done, once you have selected all the Work Categories.
The Work Categories will show under the Phase or Subphase.