Okay okay I get it! Here we go (I only know the keyboard stuff I can't help with gamepad):
Z key- Opens up the player list, where you can see who's playing and what they're doing!
F7 key- Opens up the most useful menu in the game. This is where you can actually join races and do a lot of other things like spawning and saving cars, saving your character's look and – in the Testing server – you can load up a track and drive around it on your own or with a couple of buddies! Use the up and down arrow keys to move your selection, enter to select something and backspace to exit out of a selection.
F6 key- Opens up the second most useful menu, a currently in-development menu where you can customize your character and whatever car you're currently driving! Really useful for making yourself stand out with those dollarsign wheels and hot pink paint.
F5 key- This is an experimental Character and Vehicle customization menu under development.
T key- Chat. It's uh. Where you talk. There are pretty much no chat commands at the moment, although typing…