Hi Samuel,
I appreciate all of the terminology may be confusing, so just wanted to add some clarifying comments.
There are a few mentions of PX4 in the drone world. Most of the time this refers to the autopilot software PX4. This forum is for ArduPilot, a different autopilot software. If you are using PX4 software you are better off looking at their Wiki and their forums (as Alister has linked above)