This document will help you if you are looking for answers on below questions or are looking for Official guides:
Where can I find the Admin Guides for Employee Central?
Where can I find the Implementation guides for Employee Central?
Where can I find the User Guides for Employee Central?
Successfactors - Employee Central
You can find all the BizX Admin Guides, User Guides, Implementation and Configuration Guides at: https://help.sap.com/viewer/p/SAP_SUCCESSFACTORS_HCM_SUITE or directly check for Employee Central Guides at https://help.sap.com/viewer/p/SAP_SUCCESSFACTORS_EMPLOYEE_CENTRAL (both URLs requires a login).
We recommend every administrator periodically download the current version of above guides .
Admin guide, product handbook, employee central documentation, implementation guide, user guide, reference guide, master picklist, EC help , KBA , LOD-SF-EC , Employee Central , How To