You cannot extract part09 by itself. You must have all parts (01 through the final number) in the same folder for the extraction to succeed.
Large games like Days Gone (which can exceed 60GB) are often split into smaller "parts" (e.g., .part01.rar , .part02.rar , up to .part09.rar and beyond) to make downloading and uploading easier. days_gone.part09.rar
Your motorcycle is your most important tool. You’ll need to manage its fuel and repair it constantly. You cannot extract part09 by itself
Ensure every single part file is present in one directory. days_gone.part09.rar