SureAI

I've looked on different step by step install videos and different forums but I can't seem to figure out what I'm doing wrong.
Here are some screens of my folders:

I don't know about the Steam or the english versions,
but I'm pretty sure that you should not have the Nehrim Launcher in your Oblivion folder

can you just try uninstalling both, and then reinstalling? (you won't need the Addons, just the latest patch for Oblivion)

what exactly did you try to start?
- Launcher / Nehrim with some shortcut
- Nehrim with the Launcher
- directly Oblivion(.exe) from the Nehrim folder?

if you didn't do that, try the last one, see if that does something else