The "part2" means this is the second segment of the total set. For the extraction to work, you usually need every piece in the sequence (e.g., file23.part1.rar , file23.part2.rar , file23.part3.rar ).
Many RAR archives are encrypted. You will be prompted for a password once you start the extraction of the first part. Are you having trouble extracting this specific file, or file23.part2.rar
Sometimes a specific part (like part 2) gets corrupted during download. Most download managers can re-verify the file, or you may need to download that specific part again. The "part2" means this is the second segment
Choose "Extract Here" or "Extract to file23/". The software will automatically "stitch" part 1, part 2, and the rest together into the original single file. Common Issues file23.part2.rar