Software Support Late 2013 MacBook Pro
Why does google say that the late 2013 MacBook Pro supports Catalina, but apple support says Big Sur is the most recent update available? It's running Mac OS Sierra.
MacBook Pro 13″
Question marked as
MacTracker says that the MacBook Pro (Retina, 13-inch, Late 2013) can run Big Sur, but nothing later. Apple's site confirms this.
macOS Big Sur is compatible with these computers - Apple Support
macOS Monterey is compatible with these computers - Apple Support
I don't know what your Google search turned up, or why other sites would say something different (unless perhaps they're old sites that were never updated). But I'll take Apple's and MacTracker's word as to what the real deal is.
You can get High Sierra, Mojave, Catalina, or Big Sur by following the directions here:
How to download and install macOS - Apple Support
Note that if you upgrade to either Catalina or Big Sur, 32-bit apps will stop working.