While a wok and a frying pan can generally be used interchangeably, the shape of the wok is what gives it a lot more functionality.
Most woks you see in in America have a small flat-bottomed area so that they dont tip/slide around on the stove. That flat part will work just the same as a frying pan does. As for the rest of the wok, the heat dissipates more quickly the as you go higher up on the side of it. The way to take advantage of this is by doing whats known as stir fry, where basically, your longest-cooking ingredients go in first into a super-hot wok, get mostly cooked, and then you begin adding your quicker-cooking ingredients. As you add your quicker-cooking ingredients, you stir the longer-cooking food out of the middle of the pan and up the sloping sides. With practice, this allows you to have a lot more temperature control in preparing 1 pot/ 1 pan style meals than you would with a normal frying pan, and if it's super hot like its intended to be, most of those meals will be completed in less than 5 minutes.