Stop inconsistent data at the 'entrance' before fixing it—Steps to create a dropdown list using Excel Data Validation and how to find values entered via copy-paste

When I aggregated the data, the same department was split into four."General Affairs Department", "General Affairs", "General ...

Instead of fixing Excel inconsistencies after entry, standardize the entry point with "Data Validation"

Even though it is the same person in charge, the table contains different names like "Sales Dept," "Sales," and "Sales ...