Why doesn't my LEDs turn on?
If you are doing what is in the first picture then you're doing it wrong.

You have to make sure the led is horizontal, not vertical. The signal is going through the led and not making it into ground. And your ground is in the same lane as your signal.

I think you should learn how breadboards work and then move on from there. Its pretty simple and I think you'll learn it quickly.

For your code part, instead of defining the variables, you could just use int.
 Refer to this as a starter tutorial, https://www.arduino.cc/en/Tutorial/.



This is how your wiring should look like if you followed the tutorial,