I'm not sure if gopro is a good option. Yes, you can find a lot of positive reviews on the Internet, but not so long ago I came across an article about
underwater camera for snorkeling, and there were as many as 9 alternative camera options for underwater shooting. And gopro doesn't seem to be as good an option to me as I used to think until I found out about other cameras. In short, read this article. It will make it easier and faster.