"I think it would start just like ww1 in balkans the most unstable part of europe,
countries I think are
usa,britain,germany,russia vs north korea,yogoslavia,turkey,saudi arabia"

I highly doubt the balkans will have anything to do with this and the last time i checked, "Yugoslavia" does not exist anymore. The "Yugoslavia" state was nothing more than a crappy period of time for the balkan region. These days, those countries keep to themselves.

Basically, WW3 will be Western Civilisation vs Eastern Civilisation.