I cant play fearless like this!

[Feffe]

FN is mainly because of laptops with fewer keyboard button and/or features to the laptop itself. There should be buttons on your keyboard with multible functions, which will usually be marked by blue writing or such on the keyboard. For example F1-12 or numbers. There should be a FN button next to your Windows Start button on your keyboard, which you should be able to just press and hold to activate the secondary function on these marked buttons.