Okay JesusSaves17! Here are the original pictures, and I'll tell you how I did it!
This is the original picture of the merman!
I used a 'magic eraser' to remove his head and his hair!
I then took this picture and drew the head off!
Then I used a filter to change the skin tone to better match the body!
Then I used a picture blender! I chose the merman body as the background, then the head as the foreground, and I adjusted the size to what it needed to be!