Luke was a fully trained jedi knight in ROTJ, ya ok he didn't have the order teaching him he was mostly self taught. But he was trained.
Luke was trained, yes. Fully trained is a matter of debate. Yoda and Obi-Wan didn't have near the time it would take to fully train him. Self taught? He would have to do some major communing with the Force and then get Lightsaber techniques downloaded into his brain, imo. At least it wasn't Keanu Reeves saying "Dude, I know Shii-Cho! Most Excellent!" Although, tbh the originals COULD have had better swordfights. That was the one thing the prequels pwned the OT on.