Arduino Temperature sensor with a LED

I want to program a temperature sensor with a LED using Arduino. the goal is to make a sensor, when the temperature is over than Temperature max, the LED turns off and when the temperature is small than temperature max we turn on the LED.

my problem is when I programed the void setup() as followed, the LED doesn't work, and when I comment Serial.begin (9600) the LED work but I cannot diplay the value of the temperature.

void setup() {
   Serial.begin(9600);
   pinMode(tempPin, INPUT);
   pinMode(led, OUTPUT);
}

here you find my complete code:

int tempPin = A0;   // the output pin of LM35
float Max_temp = 24.0;
int led = 1;

float  temp, cel;
void setup() {
   Serial.begin(9600);
   pinMode(tempPin, INPUT);
   pinMode(led, OUTPUT);
}
void loop() { 
      cel = readTemp(); 
  if(cel< Max_temp) {        // if temp is higher than tempMax
      digitalWrite(led, HIGH);  // turn on led
      delay(300);
     } 
     else {                    // else turn of led
       digitalWrite(led, LOW);  // turn on led
      delay(100);
  }
   Serial.print("TEMP: ");
   Serial.print(cel);      // display the temperature
   Serial.print("C ");
   Serial.println();
   delay(300);  
}
 
float readTemp() {  // get the temperature and convert it to celsius
  temp = analogRead(tempPin);
  return temp * 0.48828125;
}