Why does my button not working?

I am a new game developer, and I am making a game in unity. I have button, and the button doesn’t work at all.

Also I have a "game object" with a script (here is a part of it):

void Update()     {         if (Input.GetKeyDown(KeyCode.Escape) && isopen == false && can)         {             Stop();         }         else if (Input.GetKeyDown(KeyCode.Escape) && isopen)         {             Continue();         }                } 

And that also doesn’t work.

P.S I have 3 canvases.

I look forward to see an answer.