How do i re-write a fairy tale? it seems impossible.

Change an important detail as well as the small details. For example Cinderella. Her name was Ella when she was born both her parents died. she was sent to a cook in the castle who bought her as a slave.  There the prince fell in love with her. But she couldn't go to the ball cause she had to serve the prince and you can probably change it add more details and finish it but this is an idea.