Macbook not properly functioning after uninstalling adobe flash player

I recently uninstalled adobe flash player as I was told to do so by the flash player its self and also since it is now obsolete due to websites such as YouTube using HTML 5 etc. But ever since I uninstalled it I can no longer play any YouTube videos or even listen to music on Spotify. Does anyone know how to fix it? I also can't re install adobe flash since its no longer available.