when your in settings go to gameplay next to graphics and actually click on " game" same goes with modifiers and audio. You can play as any ingame zombies character as well! look through all of them and check out all the custom stuff you can do! hope this helps
after selecting Gameplay you will see. "audio", "Game" and "Modifiers" hover over "Game" and click it. You can also play as any zombies character. There will be a slider on the top under Brightness, It will say Field of view and a little slider you can slick and drag to increase or decrease.