This guy sabotaged the Robot Design contest, so it's time to head over to his place and teach him a lesson.
Like other NES Mega Man games, the passwords only take you as far as the first stage of the first fortress. Get the Energy Balancer and the Beat parts if you don't have them yet, then right down the password.
This level is very straightforward, with the only real challenge coming from the platforms that change their angle when you jump on them. At one point of a vertical ascent, you'll see a cracked block across a small pit, with these platforms the way to reach it. You can trash that block with the Rush Power, bue due to the spikes right overhead, this is very difficult to do, and only recommended for experts. But if you do pull it off, you get FOUR extra lives along the path!
Otherwise just stick to the traditional path. This is an easy level.
The boss is two robots that run along a wall track, dropping shots as they do so. To take care of them, turn on Rush Power and hit them with fully-charged shots when they come down to your level. Not only will it inflict a good chunk of damage, it will send them going the opposite way, out of your path. Dodge the shots they try to hit you with, and hit them with Rush Power charge shots. This isn't too tough a fight.