Understanding how contrapositive work I want to understand contrapositive clearly. I'll start by saying: "If it is sunny, then there is light". The statement is true. But now consider the contrapositive: " If there is no light then it is not sunny".  The contrapositive is false because you could create light with a flashlight.
What is wrong here?

Your conclusion about the flashlight has nothing to do with the contrapositive. You may was well say that the original statement is false because your eyes are closed. It has nothing to do with the claim.
The hypothesis of the contrapositive is that there is no light. So not only is it not sunny, but also you don’t have a flashlight, and there is no fire burning, and your car headlights aren’t on, etc etc.
Note also that even if there were light (say you have a flashlight), then the hypothesis of the contrapositive is false, so the contrapositive is true because it would be a statement of the form “F $\implies$ something” which is always true.
