The "hole" is talking about a missing spot
for an electron in the, well, call it a mobile electron lattice in certain metals. Conductivity, you know, means that they electrons are labile rather than more or less strictly localized within a specific orbital as in discrete gaseous molecules.
One analogy might be to those old-fashioned theater marquee lights:
If you look at it, at first it seems like the blacked areas are moving: in fact, it is the activity of the lights that makes it seem so.
The lit-up lights in the marquee are the electrons, the unlit lights are the holes.
When waiting to make a left turn at an intersection, we don’t really look at oncoming cars so much as the approaching ‘hole’. When the hole is crossing the intersection, we make the left turn !