simple problem

simple problem

Hello, Can anyone help me?

I have to do the below but i can't.

I need to draw on the left side of Canvas a cowboy with a gun. Once a page is loaded, a bullet will drop off the gun. The sphere will be reflected on a wall that is near the right side wall. When the ball strikes the cowboy, he will fall to the ground and a message "this was a mistake!" Will appear. The message will appear above the head of the cowboy.

If anyone can help me, i will be very thankful.