Moving two stepper motors in parallel at different speeds

Projects Programming
1 
#include <Stepper.h>

int stepsPerRevolution = 12800;  // change this to fit the number of steps per revolution
// for your motor

// initialize the stepper library on pins 8 through 11:
Stepper myStepper1(stepsPerRevolution, 2, 5);
Stepper myStepper2(stepsPerRevolution, 3, 6);
unsigned long currentMillis = 0;    // stores the value of millis() in each iteration of loop()
unsigned long pastMillis1= 0;
unsigned long pastMillis2= 0;
int interval1 = 1;
int interval2 = 1;
void setup() {
  
  // set the speed at 60 rpm:
  myStepper1.setSpeed(120);
  myStepper2.setSpeed(20);
  Stepper1();
  Stepper2();
 
  // initialize the serial port:
  Serial.begin(9600);
}

void loop() {
  currentMillis = millis();   // capture the latest value of millis()
                             //   this is equivalent to noting the time from a clock                         
}
void Stepper1(){
   if(currentMillis - pastMillis1 >= interval1){
    myStepper1.step(stepsPerRevolution);
    pastMillis1+=interval1;
}

}
void Stepper2(){
   if(currentMillis - pastMillis2 >= interval2){
    myStepper2.step(stepsPerRevolution);
    pastMillis2+=interval2;
}

}

As of now the motors do not run with that code and I can't understand why. It seems that I set everything up.

I ran them earlier in parallel with this code

#include <Stepper.h>

int stepsPerRevolution = 12800;  // change this to fit the number of steps per revolution
// for your motor

// initialize the stepper library on pins 8 through 11:
Stepper Stepper1(stepsPerRevolution, 2, 5, 3, 6);
//Stepper Stepper2(stepsPerRevolution, 3, 6);

void setup() {
  // set the speed at 60 rpm:
  Stepper1.setSpeed(120);
  // initialize the serial port:
  Serial.begin(9600);
}

void loop() {
  // step one revolution  in one direction:
 ("clockwise");
  
  Stepper1.step(stepsPerRevolution);
}

But the issue is that I want to move them at different speeds and I can't seem to get that working for some reason. i followed the tutorial to the best of my ability but it seems I am missing something

2

The setup() function is called once. When it calls Stepper1(), currentMillis and pastMillis1 are both zero, so Stepper1() does nothing. Neither does Stepper2(), for the same reason.

Then, setup() ends, and loop() does nothing useful.

So, of course the motors don't move.

3

Stepper::step blocks, so you can't use multiple steppers at the same time.
Use a non-blocking stepper library, like AccelStepper.

4

These links may be of interest.
Stepper Motor Basics
Simple Stepper Code

...R