You don't need a bunch of those things
Sound Card or Network card as all motherboards have built in chips for those. You won't get much of a benefit for from buying a separate card for either unless you have a amazing sound system or a amazing internet plan
Screws and wires aren't needed as they should all come with the case and powersupply.
Heatsink-unless you plan to overclock, if you don't plan to overclock no point in getting one because one already comes with a CPU.
You need a powersupply, that big metal box with the power wires, it's required and never skimp out on a cheap one.