Use a high-quality extractor like 7-Zip or WinRAR.
The software will automatically read the data from Part 1, jump to Part 2, and continue through Part 126 until the full game folder is reconstructed. ⚠️ Common Troubleshooting game-cyberpunk.2077.game-(61835).part126.rar
Put part1.rar , part2.rar ... all the way to part126.rar and any subsequent parts into one dedicated folder. Use a high-quality extractor like 7-Zip or WinRAR