To set the workload estimation statistics,
Project Administrator permission is needed for this action.

The workload displayed in the following features will base on the selected estimation statistics.
Nevertheless, you can still use whether story point or man-hour to track the workload on the work details pane.
Whichever way you select to estimate the workload, you can use the Time Tracking feature to record the hour spent on the work or subtasks.
Time Tracking includes two fields: Used Man-hour and Remaining Man-hour.
The Remaining Man-hour will be auto-filled according to the Used Man-hour.
To enable the Time Tracking Feature:
