My Office, Word not in German but English?

Yesterday I bought a notebook with Office 365, and activated everything.

Then I open Word or the app My Office, and everything is in English. Then I went to options in Word and stands there. German (Germany) '' Proofing not installed '

And when I click on it I will be redirected to the settings of my laptop. But everything is already in German.

How do I translate that into German?

You have to set the language and the region in German under time and language.