Because it is "part 08," you cannot open it on its own. You need the complete set of parts (e.g., part01, part02, etc.) to successfully extract the content.
: All parts must have the exact same name except for the part number (e.g., AIOURDR2DD.part01.rar , AIOURDR2DD.part02.rar , etc.). AIOURDR2DD.part08.rar
: Right-click on part01.rar (the first file) and select "Extract Here" or "Extract to folder..." using a tool like WinRAR or 7-Zip . Because it is "part 08," you cannot open it on its own
: Ensure all numbered parts (part01.rar through the final part) are in the same folder. : Right-click on part01
: Always scan extracted files with an antivirus like Avast or Windows Defender before opening them.
: If you are missing any part, the extraction will fail with an error like "Unexpected end of archive" or "Volume missing".
Are you having trouble or is the extraction giving you an error ? How to merge .part files using WinRar