I want to build a gaming PC? - 2

So it's time I've joined the PC master race. Ha. Always wanted to say that, alright so I've been wanting to get a gaming pc for a long time now. So I need some help. I don't have a single clue what I'm doing, so I'm asking if anyone knows a good build or just regular computer (absolute max $400) I want to run games like GTA 5 or FO4 or cod/boyfriend and minecraft or terraria, you know your normal games. So if I could get some advice or even an entire part list it's all greatly appreciated, thanks!