Ok and Understood - Welcome to the World of Apple !!
Like in Windows, there are upgrades that happen. Like Windows 10 version 1909 and eventually Windows 10 2H2. Similar principle applies to macOS Big Sur version 11.2 there is a Big Sur Update to Big Sur version 11.2.3. What I was trying to determine if this computer has the Most Recent UpDated installed.
There is a way outside of what I asked. On the Desktop of the Computer Upper Left Apple Icon - Sysem Preference in a Down Menu >> Software Updates and open this Software Updates. It will connect to the Apple Servers and search for any Updates to the OS. If it finds an update - it will offer to download and install. That would pretty well secure having the Most Up-to-Date version available for this computer.
If the update is available, be sure to be connected to charger.