It's impossible to know for sure who the first person to have a baby on Earth was. We don't have any records from that far back in time.
The very first humans, our ancestors, lived millions of years ago. We know that humans have been around for a long time because of fossils and other evidence.
However, we don't have any way of knowing who the first person to give birth was. It's a question that we can't answer with certainty.