Controlling fan speed with Photon and FET transistor

I’ve gathered most of the materials I need.

The last thing I’m trying to come to an conclusion about is how to drive both the Particle and the fan with the same power source.

Say I connect a 12V DC adapter to the breadboard. Could I leech 5V power from that? Maybe by using one of these, or similar? https://www.conrad.se/?websale8=conrad-swe&pi=157954&rdeocl=1&rdetpl=desktop_productpage&rdebox=box1

How could I connect a USB cable to that?