Not all at once, you can break it up into different exercises. Like 4 sets flat bench, 4 sets incline bench, 4 sets flies, etc. I don't think they mean for you to start out doing 12 sets of squats (tho honestly, if you survived, you'd feel pretty bad ass and rightly so). Just remember with any of this info, you need intensity on these. You should feel like you're having honest trouble on the last rep, and I don't mean "hmm, this is a little bit heavy" I mean "OMG I think I'm going to shit myself and vomit". Without intensity, you might as well throw the weights away and find another way to waste time.
Also, listen to what everyone else says please. I know sometimes (especially with younger guys) people ask questions not to learn but to reaffirm their own methods. These guys def know what their talking about so if you want to get big, I'd suggest taking notes.