Pirated or "cracked" versions of the game typically do not allow access to GTA Online, which is where the vast majority of the game's modern content and community reside.
Many "top" sites for these keywords bundle the text files with "key generators" or "activators" that are actually trojans, ransomware, or miners. These programs can steal your personal data or damage your hardware.
Often, these sites force you to complete "human verification" surveys. These are designed to generate ad revenue for the site owner while never actually giving you a working key. Why Official Versions Are Better