Z + Arrow Keys to do different moves when you have a copy ability. (You'll have to mess around with variables a bit to do that, though.) X to jump, Z to inhale, Tap/Hold X in midair to float, Z during float to stop floating, Down + X to slide, Down to duck. L/R to move, double tap L/R to dash.
The thumbnail is acting weird on mobile. I have been shoving out engines a whole lot, haven't I? This one is a massively improved version of an old Kirby engine I found in my unshared projects, which was a massively improved version of a previous Kirby engine. I dug this one out and made it good for Kirby and the Star Key (See, I didn't forget about it) You can use it if you provide credit.