Thus Noah did; according to all that God commanded him, so he did.” (Genesis 6:22)
Genesis 4:22 tells us that pre-Flood men knew how to craft and work with bronze and iron.
Many people wonder how Noah knew how to build such a huge Ark without modern tools and technology. But our ancestors, children of Adam and Eve and made in God’s image just like us, were not unintelligent. In Genesis 4:20–22 we read about some of the descendants of Adam and Eve. These men raised livestock, played instruments like the harp and the flute, and worked with metals like bronze and iron. All of these things take intelligence! If they were able to do these things just a few generations after Adam and Eve, imagine what they could have accomplished in the approximately 1,700 years before the Flood!
Think about it: only just over 100 years ago the first successful airplane flew and now we have jet engines flying all around the world. We’ve even flown a few manned missions to the moon! Just over 30 years ago, the Internet got started and now we can look up almost anything from almost anywhere in the world. Only just over 20 years ago the first smartphone came out and now smartphones can do incredible things. All of these things have happened in the last century. We can’t even imagine what they might have invented before the Flood when people lived for hundreds of years—imagine if geniuses like Albert Einstein or Isaac Newton lived for hundreds of years. People in the pre-Flood world that was destroyed in the Flood would have had incredible technology and tools.
The idea that our ancestors were unintelligent brutes who slowly had to learn how to make tools from stones does not come from the Bible. That’s an evolutionary idea based on the belief that man evolved slowly from ape-like ancestors. But in the Bible we have the real history of humanity and we know that people were intelligent right from the very beginning. So it was no problem for Noah to build the Ark just like God told him to so he could save himself, his family, and the animals.