Noah (also Noe) was the man of the godly line of Seth. He was selected from among a godless society to build the Ark that protected him and his family during the Great Flood. Though he proved to be godly himself, he was chosen to be the father of a new mankind by the grace of God who revealed to him the plan to destroy the world with a flood.
For at least 100 years Noah would work on building a large boat in which he was to escape the flood with any who would believe God's warning. He had been also told to also take on all the animals that breathed air (except the whales which populated the sea).
When he was 600 years old, he and his family, along with the animals and enough food for at least a year, climbed into the ark and prepared for the judgment of God upon the earth. A little over a year later, they stepped out onto dry land. Noah would live for another 350 years.