Also Read: Permanently delete/remove Facebook account
If you get for example Candy Crush game notifications then you can simply block that game on your account, just go to account settings and from left panel select Blocking.
Now you can block apps or app invites by entering its name in the text box.
Or when someone from your friends invites you to game you can go to Games section from Facebook's main page and in invites you can see the games your friends invited you. Simply press the "X" button to remove it and you can see the highlighted text that you can instantly block that app.
How to Schedule/Auto Post Birthday wishes on Facebook
There is a way to completely turn off apps on your account, but that time you can't open any Facebook app and can't register on any website with Facebook if you see the feature, because that time you are opening that web sites app.
But if you don't really care about that and what to completely disable it then you can do it with next steps.
Again go to account settings and from left panel select Apps. And there you need to edit "Apps, Websites and Plugins" settings by pressing the Edit button. And in pop out window press on the Disable Platform blue button.
Now you will not receive any kind of app notification.