Good night....
I need help, I'm not a very professional progammer and I have some troubles with a sketch. I hope somebody can help me
You do need help, for example, with reading the thing at the top of the forum section you posted in, which says "NOT for problems with your project"
Also, read the sticky "how to use these forums" guide - post error messages as text, using code tags, as described there. Don't ever post screenshots of error messages or text in general (not just here, everywhere) unless it's not possible to copy the text and post it as text.
In any event, the error you have is that you are including a library AFMotor but you have not installed it, or have not installed it correctly. It should be located in a folder called AFMotor, inside (your documents folder)/Arduino/libraries.