If you are just looking to power that board then you have 5v and 3v available from the pi. Reference this pin out
The + (positive) should be either to 3v or 5v depending on what the board needs. And the - (negative) can go to a ground pin
Discussion
On the other hand, if you want to connect an LED to the gpio pins and control from the pi, there are many projects for that and this one directly on the raspberry pi site walks you through it
https://projects.raspberrypi.org/en/projects/introduction-to-processing/7
Thanks so much!!