How do I create a new Desktop ("Space") on macOS using only the keyboard?
I'm not sure there are any native solution to this problem, but there are third-party applications that can help.
One of them is BetterTouchTool, a program that can aid operating a Mac in several ways.
Another is Hammerspoon, but that requires you to write some code yourself.
I doubt these are the only two, only the two I know of.