We evolved from an early ape that was also a common ancestor of us and the existing apes.
From that early ancestor, the branch that led to us ended up in an area that was not a dense jungle--probably a result of climate change that caused an open woodland because of reduced rainfall--while the other branch that led to the present-day apes remained in dense jungle.
The open woodland that our early predecessors lived in had different environmental pressures that resulted in a different mode of living compared with the ape lineage. The environmental pressures of the open woodland ultimately led to bipedalism and tool making, and we are the result.
The environment of the other lineage that remained in the jungle resulted in further adaptation to the jungle environment, thus leading to the great apes of today, the gorilla and chimpanzee.
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Baylee, in answer to your comment below. It was an early ape. All apes are ape-like, since the living apes have variation in body types, though with common features. The present-day apes consist of the lesser apes (the siamang and the gibbon), which had an earlier common ancestor with the common ancestor of us and the great apes (the orangutan, the two species of gorillas, bonobos, and chimpanzees).