Wokwi - Online ESP32, STM32, Arduino Simulator

//Change Line Nos.3,7,28
//Wokwi
#include "WiFi.h" 
//#include <ESP8266WiFi.h> //NodeMCU
#include <WiFiClient.h>
#include "DHT.h"
#define DHTPIN 2 //D2
//Wokwi
//#define DHTPIN 4 //D2
#define DHTTYPE DHT11
DHT dht (DHTPIN, DHTTYPE);
WiFiServer server(80);
//NodeMCU
static char celsius [7];
static char fahrenheit [7];
static char humidity[7];
void setup() {
  Serial.begin(9600);

  dht.begin(); 
  WiFi.mode (WIFI_STA);
  WiFi.begin("Wokwi-GUEST", "");
  //WiFi.begin("ssid","pw");
  Serial.println("");
  while (WiFi.status() != WL_CONNECTED) {
    delay(5000);
    Serial.print(".");
  }
  Serial.println("");
  Serial.print("WiFi connected");
  Serial.print("IP address: "); Serial.println(WiFi.localIP());
  server.begin();
  Serial.println("HTTP server started");
}
void loop() {
  WiFiClient client = server.available();
  if (client) {
    Serial.println("New client");
    boolean blank_line = true;
    while (client.connected()) {
      if (client.available()) {
        char c = client.read();
        if (c == '\n' && blank_line) {
          delay(2000);
          float h = dht.readHumidity(); 
          float c = dht.readTemperature(); //Celsius
          float f = dht.readTemperature (true); //Fahrenheit
          if (isnan (h) || isnan (c) || isnan (f)) {
            Serial.println("Failed to read from DHT11 sensor!");
            strcpy(celsius, "Failed");
            strcpy(fahrenheit, "Failed");
            strcpy(humidity, "Failed");
          }
          else {
            float hif = dht.computeHeatIndex(f, h);
            dtostrf(f, 6, 2, fahrenheit); 
            float hic = dht.computeHeatIndex(c, h, false);
            dtostrf(c, 6, 2, celsius);
            dtostrf (h, 6, 2, humidity);
            Serial.print("Humidity: "); 
            Serial.print(humidity);
            Serial.print("% Temperature: ");
            Serial.print(celsius);
            Serial.print("C ");
            Serial.print(fahrenheit); 
            Serial.print("F Heat Index: ");
            Serial.print(hic);
            Serial.print("C ");
            Serial.print(hif);
            Serial.println("F");
          }
          client.println("HTTP/1.1 200 OK");
          client.println("Content-Type: text/html");
          client.println("Connection: close"); 
          client.println();
          client.println("<!DOCTYPE HTML>");
          client.println("<html>");
          client.println("<head></head><body> <h1>ESP8266 -Temperature and Humidity</h1><h3>temperature in Celsius: ");
          client.println(celsius);
          client.println("*c</h3><h3>Temperature in Fahrenheit: ");
          client.println(fahrenheit); 
          client.println("</h3><h3>Humidity: ");
          client.println(humidity);
          client.println("</h3><h3>"); 
          client.println("</body></html>");
          break;
        }
        if (c == '\n') {
          blank_line = true;
        }
        else if (c != '\n') {
          blank_line = false;
        }
      }
    }
    delay(2);
    client.stop();
    Serial.println("Client disconnected.");
  }
}