Answer 1

Some sad answer here.... Unfortunately, when Windows 2000 came out, QBASIC didn't come with the OS any more.

While this may be significant for an architectural reason (Win2K and later's based on the Windows "NT" kernel, which does not have a DOS backend to exit from protected mode into)...the bigger issue today is that bit depth is "one back" only: that is, a 64-bit OS has a 32-bit subsystem for backwards compatibility, but the 16-bit subsystem is long gone (and that's where QBASIC was).

There are independent updates written for later OSs, but I don't believe they're official Microsoft :/

For what it's worth, you can still play with QBASIC in DOSBox, or an emulated x86 system in-browser though (start MSDOS 6.22, type QBASIC):
https://copy.sh/v86/