Hello everyone i am making stm32 nucleo project in arduino ide. I used to use Ardunio and i can easily take output from any pin however now i am using stm32 nucleo l073 rz and i cant take ant output. I want to make simple thing. When i pressed the button if conditions are satisfied my water pump have to be work in any speed i dont want to control fan speed. This is my code block thanks. When i pressed button all things are worked except engine.
And there are many pins stm i cant find the proper one for engine

DATASHEET

#include <LiquidCrystal.h>

#define LCD_RS PB8
#define LCD_EN PB9
#define LCD_D4 PA8
#define LCD_D5 PB10
#define LCD_D6 PB4
#define LCD_D7 PA10

#define trigPin PA9
#define echoPin PA7

#define buton1 PA9

#define motor PC4

LiquidCrystal lcd(LCD_RS, LCD_EN, LCD_D4, LCD_D5, LCD_D6, LCD_D7);

long duration, distance;

void setup() {


  


lcd.begin(16, 2);
lcd.print("SENSORED WATER");
lcd.setCursor(3, 1);
lcd.print("DISPENSER");
delay(2000);
lcd.clear();

pinMode(buton1, INPUT);
pinMode(motor, OUTPUT);

Serial.begin(9600);
pinMode(trigPin, OUTPUT);
pinMode(echoPin, INPUT);





}


void mainFunction(){
  Serial.print("Button State: ");
  Serial.println(digitalRead(buton1));
lcd.print("CHOOSE AMOUNT");
lcd.setCursor(0,1);
lcd.print("TALL VENTI GRANDE");

if(digitalRead(buton1) == 1 ){
  if(distance <=5){
  lcd.clear();
  lcd.print("Filling started");
  digitalWrite(motor, HIGH);
  delay(5000);
  digitalWrite(motor, LOW);
  lcd.clear();
  }
  else{
lcd.clear();
  lcd.print("BARDAK KOY LA!");
  delay(2000);
  lcd.clear();
  }
  
}




}





void loop() {

  mainFunction();


   
 
}

When i pressed button engine needs to be start.