Given this general principle of Scripture, we should expect similarities in the Genesis account of the flood and other accounts found in other cultures. We might even see that these other accounts predate the writing of the Genesis account. But that is not a problem when we see that it was God’s purpose to tell His people how the flood actually came about. It was not just some natural event, but God’s judgment on the wickedness of the earth.
Ancient Origins has an article of how the Hindu Flood Legend is very similar to the story of Noah found in Genesis. You can read the story by following the link here. This Hindu story is not really a problem for Christians since it stands to reason that all the nations of the earth descended from Noah and his three sons after the flood. We would expect there to be stories of the flood coming from every tribe and nation. It is confirmation of the flood.
The temptation on the part of many of the critics of Christianity is to say that Moses, who wrote about the story of Noah in Genesis, was merely capitalizing on the the story found in other traditions. That is partly true.
Noah was, by God’s hand, setting the record straight for God’s people. Remember his original audience are the people he lead out of Egypt during the exodus. He is writing to them, and us, showing their origins and how it was that they came to be. When he gets to the story of Noah, he is telling the story from God’s point of view. We see this confirmation from the article cited above.
According to the Hindu legend, it is Noah (Manu) who saves the people from the flood. But according to Genesis, it is God who saves Noah and his family through the flood. The true story is of God’s hand in delivering his people. It is about God’s mercy to Noah, not Noah’s cleverness to escape the coming deluge.
These small facts are actually confirmation to us that the Bible truly is God’s word written by God through apostles and prophets.