5 different ways to Blink an LED using Arduino (+ Bonus)
Multiple Blinking LED on the Arduino : 4 Steps - Instructables
Arduino - Turn LED ON and OFF With Button - The Robotics Back-End
Simple LED based Projects using Arduino-with Circuit Diagram and Codes
Amazon.com: ELEGOO 3mm and 5mm Diffused and Clear Assorted LED Kit 5 Colors with UV, RGB CA, Fast Flashing Compatible with Arduino (Pack of 350) : Industrial & Scientific