You can use a 3D printer to create replicas of items made in Minecraft. YouTuber ItsJustJumby did the opposite: he built a virtual 3D printer using Minecraft. Actually he built a 3D modeling program, a computer and a 3D printer inside the game.
You can say that Minecraft itself is a kind of virtual 3D printer: you stack tiny blocks in layers and eventually end up with a 3D object. But ItsJustJumby’s setup is more automatic and even has a crude user interface. I’m not going to pretend to understand how his computer processes the instructions, but I can tell that it both makes 3D models and builds the final object out of wool blocks.
Now all that’s left to do is 3D print his 3D printer.