What's the difference between Potential energy ($mgh$) and gravitational potential energy ($-\frac{GMm}{r}$)?

Question

Yeah one is for measuring potential energy between the objects of two masses $M$ and $m$
We recently started studying about gravitation and I'm really confused when swtiching back and forth, or can we derive $mgh$ from $-\frac{GMm}{r}$? we derived $mgh$ through work done formula, he recently referred "Gravitational work" as $mgh$. It's really confusing.