how come it o hard to get adobe flash player to work on window 8.1?

The problem ISN'T Flash Player, and it ISN'T Windows 8.1 (not completely anyway).
It's that abomination they call a browser. Internet Exploder 11, which installs by default if you upgrade from Windows 8, and is forced down your throat if you're gullible enough to buy a new PC with 8.1 on it.

Sites and pages can't recognize the browser, so they don't recognize any of the plugins, like Flash Player. So far, Microsoft has made NO indication that they have any plan to fix it soon. They refuse to admit their garbage is garbage.

Microsoft's recommendation is to use Compatibility View for affected pages, and "pretend" you're using an different browser. Trouble with that is it has seen limited success at best, and you have to individually enable it for EVERY page that has problems.

I'm not big on "pretending" so I recommend actually using another browser.

Firefox (from Mozilla)

Opera (from Opera)

Safari (from Apple)

Chrome (from Google)

ANY of those will work where IE11 won't, with the Flash Player Plug-in (For all other browsers), and Chrome doesn't even need that because it has its own Flash Player plugin built in.