Multi-part archives (like .part1.rar , .part2.rar , etc.) require every single segment to be present in the same folder.
If you are looking for the official version of the game, it is available on platforms like Steam and GOG, which handle the installation process automatically for you. ANNO.Mutationem.v1.04.02.part2.rar
Because this is a .rar part file, you won't be able to extract the contents using only this piece. To successfully access the game files, you need to: Multi-part archives (like