When I was yesterday doing research around How long does it take, before the details of an EU parliament decision get published? I figured, that I had some conceptional misunderstanding of how the EU is actually running their business.

I checked their website to try to get an better idea of this, but the general information are quite... superficial. So no real insights and no clue where to start digging for deeper information.

So I am asking here now, what are the different functions the EU exerts, to settle laws, rule regulations and decide other things I might not be aware of. And especially, what options do I have to review the decisions having been made in their different functionality and how individuals decided in such regards?