God’s time is different from our sense of time. The Bible says it took a few days for him to create the earth, right? Well, for God it was a few days. For us, it was billions of years. During those few days (aka billions of years), dinosaurs existed and animals got created. Then the dinos got wiped out and Adam and Eve got created. God is an immortal entity, so of course a billion years would be less than a week for him. He’s timeless.