To use Cinema 4D for free legally:
In the software world, a "portable" app is one that runs without installation, often from a USB drive. Maxon does not create these. Any "Cinema 4D Portable" found on torrent or "warez" sites is a modified by third parties. Why to avoid unofficial portable versions: cinema 4d free license portable
The Ultimate Guide to Cinema 4D: Free Licenses, Portability, and Alternatives To use Cinema 4D for free legally: In
Maxon uses a "Maxon App" manager for installation. cinema 4d free license portable
If your goal is to run it from an external drive without installing it deeply into the system OS: