World War 3 is not likely to happen. All of the major superpowers(USA, China, and Russia) know that war wouldn't be good for either side. More than likely, everything will be worked out without war. What good would a war with the United States do Russia? It wouldn't. They know it, you know it, we all know it. It would just kill millions of people and get us absolutely nowhere..
Correct there may be some proxy wars where the world powers fight each other indirectly to raise their influence in a region but an open conflict between superpowers is not going to happen for the simple reason a conflict like that will destroy the entire world.