Its really a emergent problem because its part of the last assignment.
ClaudiusMa's picture:
There are two lights shown in that picture. The one that is labeled "ON" is the power indicator and will always be on when the Arduino board is powered.
The one that is labeled "L" is connected to pin 13. You can turn it on and off using digitalWrite() on pin 13. See:
I recommend spending some time with File > Examples > 01.Basics > Blink and the associated tutorial:
Note that the code uses LED_BUILTIN instead of 13 but it's the same thing because LED_BUILTIN is set to 13 on the Uno. This is just an easy way to make the Blink sketch work on all Arduino boards, some of which have the LED on a different pin than 13.
THANK YOU