Help Please Latch Code to button

[Mushy Cereal]

Hello I am trying to latch my code to my button so when I push the button the stepper motor spins, but I am slow and I am unsure how to do that please help.

// Include the AccelStepper Library
#include <AccelStepper.h>

// Define pin connections
const int dirPin = 2;
const int stepPin = 3;

// Define motor interface type
#define motorInterfaceType 1

// Creates an instance
AccelStepper myStepper(motorInterfaceType, stepPin, dirPin);

const char BUTTON_PIN = 8;
bool pressed = true;

void setup() {

myStepper.setMaxSpeed(4000);
myStepper.setAcceleration(250);
myStepper.setSpeed(100);
myStepper.moveTo(600);

}


void loop() {
// Read button
bool currentState = digitalRead(BUTTON_PIN);

if (currentState == pressed)
{
if (myStepper.distanceToGo() == 100)
myStepper.moveTo(-myStepper.currentPosition());

// Move the motor one step
(myStepper.run()

}

}