Hello i´m new here and i have buy Cyberpunk 2077 in Sale and got a Key from an another Website.
(btw i´m sorry im from Germany and cant really good english^^ maybe anyone can help me^^)

So my question is.. can i change the language somehow ingame or somewhere?

I dont know.. but there is just a English Button

You already got the game installed?

From the main menu, click on Settings, and then the Language tab.

I haven't played around with this myself, but something to try:
If Audio is English-only, go to your CP77 install folder and find the file called
goggame-1423049311.info

Open it in Notepad and change "English" to "German"
And the "en-US" to "de-DE".

The game must be closed when editing the file.

Or this could be a great way to learn English. ;)
I took a dictionary and 7 seasons of Top Gear UK to get the British rather nailed down myself, as opposed to the "howdy, pardner" American - which according to my english teacher in 8th grade, 25 years ago, wasn't English.

The German version SHOULD have been downloaded by default. If not, you can go to "Manage Installation -> Configure" in Galaxy and change your language. An additional download for the German audio, and you will be able to switch between German and English, as well as all the text changes you already have in the ingame menu.

There is no additional download for the German language. You just need to edit a config file.
https://www.gog.com/forum/cyberpunk_2077/change_language/post2