Only umpteen years late, I bring you the
QBasic Online Help Index — https://scruss.com/qbasic_hlp/
It’s the QuickHelp file from Microsoft’s ancient-but-still-useful QBasic interpreter for MS-DOS. I converted it to HTML, and made some minor cleanups so it would work better on the web.
So if you’ve got a hankering to understand the parameters for MKSMBF$ or know the syntax of PRINT USING, I’ve got your back.