Can access wordpress dashboard but it does not work

I hope someone can help me. I can access my dashboard but when i try to access anything else it gives me the error “Oops! That page can’t be found.
It looks like nothing was found at this location. Maybe try a search?”
If you click on pages, themes or anything it gives you that error

• This topic was modified 4 years, 5 months ago by Jan Dembowski.

The page I need help with: [log in to see the link]