Which activities must you configure before running a payroll?

 Before running a payroll in SAP HCM Payroll for SAP S/4HANA, you need to perform certain activities. These include:

Generate Payroll Periods: Payroll periods are essential as they define the frequency of payroll runs. They could be weekly, bi-weekly, monthly, etc., depending on the organization’s policies.

Create Control Records: Control records in SAP HCM Payroll are used to control the payroll status of an employee or a group of employees. They ensure that no changes can be made to master data or time data affecting the payroll past or present during a payroll run1.

Creating organizational units and assigning cost centers to positions are not directly related to the configuration needed before running a payroll. They are more related to the organizational structure and cost accounting respectively.

References = 

https://learning.sap.com/learning-journeys/get-started-with-sap-hcm-payroll/running-payroll_e1629f8b-5236-4a89-af07-6531cb316d9b