I'm doing a research paper on whales.

I need to know how they lost their legs and went to the waters. I also need to know why they went to the waters.

You probably want to look at topics like the evolution of whales... good luck searching!

I think their legs turn into the fins and the hands turn into the pectoral fins and they need fins to adapt to their new oceanic environment. They probably go to water because they have problems living on land and do much better in the water? You'll have to do some research on that.