If you don’t own GTA V, the launcher will still install, but you’ll need to purchase the game to actually run GTAVLauncher.exe successfully.
Remember: The only safe way to get GTAVLauncher.exe is through the official Rockstar Games Launcher, Steam, or Epic Games, using their built-in repair functions. Never trust standalone download sites.
The file is the core executable used to start Grand Theft Auto V and the Rockstar Games Social Club on PC.