Yes, in theory, Quantum physics allows matter and light to behave like a wave (so a particle can be everywhere at once) or a particle (so it’s in one particular place). But it can’t really be both at once – once you’ve observed a particle in a specific place it can’t be everywhere else as well!
Sure. There are a few ways that quantum mechanics lets something be everywhere (or at least several places) at once. One way is the Heisenberg uncertainty principle. It basically tells us that the more you know where something is, the less you know about how fast it’s going. Similarly, the more you know it’s speed, the less you know about where it is. So if we know pretty much exactly how fast the photon is going, it will be spread out completely.