The "CS7" name is likely a mix-up between two distinct eras of Photoshop:
Finding information about "Portable Photoshop CS7" can be a bit tricky because as an official product from Adobe. Portable Photoshop Cs7
The last version with a perpetual license before the subscription model began. The "CS7" name is likely a mix-up between
Portable versions are unofficial, modified versions of the software designed to run without an installer. Photoshop CS6 vs 2021! - 28 Reasons to Upgrade Portable Photoshop Cs7
The seventh major version, known for its speed and simplicity. It is often made "portable" because it is lightweight enough to run from a USB drive.