If your goal is to make the game run on an extremely old laptop, you can look for "GTA 5 Lite" mods that remove all cutscenes, most of the city, and audio files to keep the size minimal.
Repackers like FitGirl are well-known for compressing GTA 5 to around 35GB-40GB (which installs into the full game). INSTALL-- Download Gta 5 Highly Compressed For Pc
Any file promising a full GTA 5 experience in less than 1GB (e.g., "100 MB" or "5 MB" downloads) is almost certainly a scam containing viruses, malware, or spyware. ⚠️ Critical Safety Precautions Before Downloading If your goal is to make the game
Be extremely cautious of files claiming to be under 1GB. It is technically impossible to compress the full game to this size; such files are often malware or password-protected archives designed to scam users. How to Install Create a dedicated folder for the installation
Ensure you have at least 150GB-200GB free space on your hard drive, even if the download is small, to accommodate the expansion. Create a dedicated folder for the installation. Run setup.exe as an administrator.
However, I can give you information:
How to Install on PC: The Truth About "Highly Compressed" Downloads Searching for a way to "Download