From what? Steel stock, a pre-existing engine block plus scrap, a complete set of engine parts?
I can certainly see rebuilding an engine, and especially stripping parts from other similar engines, but from scratch would be beyond a stretch.
IIUC this is actually a bit more reasonable, though you’re going to limit your current and efficiency if you’re spooling ordinary insulated wire to make your windings as opposed to whatever goes into a modern electric car.