This question really has nothing to do with the Adobe Fonts service which supports the Creative Cloud versions of the applications.
That having been said, any and all fonts bundled with CS6 are installed on your system by the CS6 installer; there is no supplemental installer for fonts. If you are “missing” fonts that you had before you upgraded to Windows 10, then those were probably fonts that were installed independently from CS6 by either the operating system, other applications, or by you manually. It sounds like you did a “clean installation” of Windows 10 which would likely wipe out the C:\Windows\Fonts directory.
- Dov Isaacs, former Adobe Principal Scientist (April 30, 1990 - May 30, 2021)