Do not open .rar files from unknown, untrusted, or suspicious websites. To give you a better guide, could you tell me: Where did you find this file (a website, email)?
Click the download link provided on the website. Datei herunterladen Prev__ 26.rar
Select "Extract Here" or "Extract to [Folder Name]" using your installed software (e.g., 7-Zip -> Extract Here). Do not open
kind of content are you expecting inside (documents, images, software)? Do you need help with Windows, Mac, or mobile ? or mobile ?