You cannot open this file by itself. To extract its contents, you must have all preceding parts (e.g., .001 through .013 ) and any subsequent parts in the same folder.
The .014 extension indicates this is the 14th segment of a multi-part archive. PnAoil.7z.014
The file is a specific split archive part of a larger compressed file, likely created using the 7-Zip utility. Understanding the File Type You cannot open this file by itself