@saraSKELLINGTON, with all due respect, your question makes it clear that you don’t actually understand how evolution works.
1. Humans didn’t evolve from monkeys. We evolved from apes. Our closest relative is the chimpanzee (an ape). This means that if you trace our ancestors back, and trace modern chimps’ ancestors back, eventually you’ll find a “common ancestor.”
This shouldn’t be hard to believe, as chimpanzees are very similar to humans. They use tools. They have distinct cultures. They have extremely complex social relationships. They are altruistic, and they go to war with each other. They have different vocalizations that represent different things. Also, 95–99% of our genetic material is identical to that of a chimpanzee.
2. You asked why there are still monkeys if humans evolved from monkeys. This simply isn’t how evolution works. You seem to believe that evolution is a “ladder,” where each species evolves into a “superior” one and the old one disappears. In fact, evolution works more like a “bush.” Old species do not disappear when new species evolve.
Why are there still monkeys? Because monkeys are still adapted to their environments—mainly tropical rain forests. Similarly, there are still fish in the water. Amphibians (frogs, toads, salamanders) evolved from fish to live on land, but why would that mean fish would disappear?
3. I think you need to re-examine why you believe what the Bible says. You are talking about the book of Genesis, right? Genesis also says the sky is a solid dome that holds up an ocean. It says the sun was created after the earth, and that the sun, moon, planets and stars are all “set” in the dome of the sky. Later, God opens up the “windows” in the sky to let down the floodwaters.
Genesis is Mesopotamian mythology. There are Babylonian and Sumerian myths that say the same thing that are older than the Bible. Many Babylonian myths describe how sky gods made humans from clay. In fact, much of the Bible’s flood story—right down to the details about the ark and letting out birds—is lifted from an older Akkadian myth called the Epic of Atrahasis.
You should ask yourself why you trust ancient Mesopotamian mythology more than modern science.