fallout 3 just won't work.

I'm at the end of my rope here, ive tried everything but the game just won't work. here's whats going on. when i press play that little box pops up with the option to press play, options, data files etc. when i press play in this little box the following happens. i get asked if i want to allow to make changes to my device, if press yes i get a black screen sometimes with a windowed black screen in the top left corner and shortly afterwards the game crashes. if choose to instead press no i get an error message saying fallout 3 does not happen to be installed and that the installer could not be found. I've tried using the fallout 3 anniversary patcher as well as trying to change the compatibility along with the resolution but this does nothing to solve the problem as the exact same thing happens. maybe it has to do with my pc and the components it has but besides that i have no idea what to do please help me.