It’s pretty easy to break water down, but it’s also super easy to make it - just burn anything organic.
Usually you can’t see the water being formed, but there’s actually a really common example: car exhausts on a cold day. If you notice a bit of water dripping out of the tailpipe of the car in front of you at a red light, that’s actually the moisture in the exhaust fumes condensing on the cold tailpipe.