You're correct! Each limb is a separate model, and I made sure the origin of each model was the point I wanted them to rotate around.
If you want to look at how to animate a model with skeletons, you can take a look at my other 3d game Grand Beetle Run. That one uses iqm models with the anim9 lua library. Theres a lot of tricky steps, so I'd only recommend that approach if youre going to do something animation heavy.