Basically if you have ever played Undertale, then you would know that when you are fighting a monster and you go to the 4 button that allow you to interact with them, you would know that unlike when you are dodging attacks, you can only blink to the other said button.
What I mean by this is say your soul is on the item button, how do I make it so that you can not just move around as you please, but make it so that if you use a and d, you can go to the other buttons, but you can not change elevation, just your x position and you can only go to those four points