Understanding Evolution?

After learning a little bit about evolution realize why many people believe in this form of creation. There were many names that are hard to understand. There is a family tree for evolution called a phlyogeny which explains what creatures evolved from the past. Clades are branches from the phylogeny which show which animals are related to eachother. What i dont understand about evolution, and maybe somebody can inform me, is if we came from monkeys or chimpanzees why are both of us still here? It seems to me that one of us shouldnt be here. If we are here the chimps shouldnt be because they evolved into us. This is one phenomena that i dont understand. CHAKS TAKE