You must have every part of the set (e.g., Part 1 through Part 5) in the same folder.
v1.2.1 indicates a specific update or patch level of the game. WW2.Rebuilder.v1.2.1.part4.rar
Software like WinRAR or 7-Zip is required to recombine them. You must have every part of the set (e
Files named in this specific format (Version numbers + Part X) are common on third-party file-sharing sites and "repack" communities. WW2.Rebuilder.v1.2.1.part4.rar
WW2 Rebuilder is a simulation title where players clear debris and rebuild European cities (like London, Hamburg, and Essen) following the destruction of World War II.