Yes the hotend heats up and has molten plastic inside it and it gets pushed out the nozzle. I’m honestly not sure why they offer all those different versions as accessories. It includes a hotend and 0.4mm nozzle.
If you have a catastrophic issue it’s possible for the hotend to be clogged completely, but that’s never happened to me. It comes with a declogging tool which is just a long pokey wire to push up through the nozzle while it’s hot to clear it.
The nozzle itself can unscrew from the hot end and be replaced because it wears out over time from filament chipping away at it.
Also, you might want different nozzle diameters depending on what you’re printing. You can just buy spare nozzles without an entire hotend.
It comes with 0.4mm and they offer a range from like 0.2-1.0mm. The smaller nozzles print slower and more detailed while the larger nozzles are faster with lower resolution.
You’re already on hundreds of cameras by walking into any airport in the world. Do they need your consent to run facial recognition software on the security footage?