you can adjust them in a menu you bring with “del” button and press “ok&save” to keep your modifications saved, if its just fov you are after and vorpx keeps resetting fov adjustments you did you can disable automatic game settings changing by vorpx in vorpx menu window from tray.
I havent tried cod games myself, but Ive seen people mention 3rd party mod to adjust fov, you probably are missing that one, vorpx has some hacky fov enchantments but usually its better not to touch them since game might not even render objects in increased fov area.