THE BASIC PRINCIPLES OF RIDDLE

Q: My pores and skin is green and slippery, I've four legs and webbed ft, I hop on land and swim underwater, I love bugs and tiny fish to try to eat. What am I?Problem: Completely transform the word "CAT" into the term "Doggy" by changing 1 letter at a time, with Every step causing a valid English word.Riddle: A horse was tied to your rope five met