The .part3.rar extension indicates this is the third volume of a split archive. To extract the contents, you generally need all preceding and subsequent parts (e.g., part1, part2, etc.) in the same folder.
If you are attempting to access the data within this file, you can use standard archive utilities:
Ensure you have the full set of files. If part 1 or 2 is missing, the extraction will fail.
As with any .rar file from unknown sources, it is recommended to run a virus scan before opening, as compressed archives are often used to distribute malware. Do you have the other parts of this archive , or The Panther-Lair Show - Apple Podcasts
Software like WinZip , WinRAR , or 7-Zip are required to open RAR files.