The final official service pack was . What most users and enthusiasts refer to as "SP2" is actually the Convenience Rollup (KB3125574) , a massive update package released in 2016 that bundles almost every update from the release of SP1 through April 2016. The Evolution of Windows 7 Updates
Since Microsoft has officially ended support and removed most direct download links from their primary site, users must rely on reputable archives or legacy tools.
To get your 64-bit system up to date safely, follow these steps:
Use tools like certutil -hashfile <filename> SHA1 (Windows) or sha1sum (Linux) to verify.