Arduino

Is a programming language used in Electronic, based on C++

Libraries

HTTP POST

Use one of the client library, like WiFiClient

Complete example of a POST to a Webserver

IPAddress server(10,0,0,138);
String PostData = "someDataToPost";

if (client.connect(server, 80)) {
  client.println("POST /Api/AddParking/3 HTTP/1.1");
  client.println("Host: 10.0.0.138");
  client.println("User-Agent: Arduino/1.0");
  client.println("Connection: close");
  client.print("Content-Length: "); client.println(PostData.length());
  client.println();
  client.println(PostData);
}