Press X to do a cool animation of Cap'n toad turning. (I took inspiration from a cancelled Cap'n Toad game made by @juliangamer524 for the turning animation: https://cocrea.world/gandi/project/1723457769452912642) Ok in the story mode, there's not going to be doors as the end of a level, there's going to (maybe) be stars. But, I am planning that in one of the last levels of the game, you have to press X to go through a door / elevator.
Credit to @juliangamer524 for the door sound. Credit to @juliangamer524 for the original Cap'n toad design, I just edited him and made him in my style.