In this video tutorial I will show you very quick method on how to create multiple language versions of Revit.
STEPS:

Find the Revit icon on you desktop. Right click and select properties.

Modify the path by changing the language code. All language codes you may find here: https://autode.sk/2UhzaFt

Click ok. Now the Revit interface should be in the selected language.
Tip: You can also create multiple versions of Revit by simply duplicating the Revit icon and applying a revit language code.