When you arrive in the calculation screen, it is empty:
Enter the number of hours on the No. of normal hours item in the Employee Share column. (In the case of quantity items, it is not necessary to enter anything in the employer column).
If you want to pay 12 hours, type 12 in the employee share and press the tab key to validate:
Click on Compute.
The calculation is done according to the data stored in the employee management: