You can like use arrow key and you have 5 lives you lose a life if you get hurt, if you run out of lives you die. To win, jump on whoever you are fighting 5 times, You cannot hit them while they are jumping, when they jump then hit them as soon as they touch the ground. For some reason this is on trending when you search EarthBound
Credit to @Brad-Games for the original Project, and credit to @PixelJCoder and @King8766. Music is from Earthbound and Undertale