Copyleft licenses require that derivative works maintain that same license. Not all the Creative Commons licenses are copyleft. CC-BY only requires that attribution be given in the derivative work. That’s the one YouTube offers as an option for uploads.
If you want your video to be copylefted, you should use one of the SA (share-alike) licenses. See https://creativecommons.org/share-your-work/cclicenses/
Installing Linux after Windows should be fine without disconnecting drives.
The reverse is troublesome. Microsoft’s installer is all too happy to shit on your drives, even the ones you’re not using for installation. But Linux installers are much more friendly to dual-booting and all kinds of complex setups.