Response from ESP8266 is returning unknown characters
String command = "POST /webservice/v1/dispositivo/atualizar_data_requisicao HTTP/1.1\r\n";
comando += "Host: " + SERVER + "\r\n";
...
esp8266.println(command);


I suspect this is just a typo because it shouldn't compile.  But you are adding all the HTTP headers to commando not command.

Usually the ? means that the character is unprintable.  So to help diagnose the issue display the integer value for each character that is returned.  Something LIKE this (I've never used a String before so length() might not be right)

Serial.print("Request response: ");
Serial.println(response);
for (int index = 0; index &lt; response.length(); ++index)
{
   Serial.print (response[index]);
   Serial.print (" ");
}


If you want to program the ESP directly then have a look at these guides, they should give you the general idea.  Its usually as easy as programming an UNO once you are setup.

http://www.whatimade.today/esp8266-easiest-way-to-program-so-far/
https://learn.adafruit.com/adafruit-huzzah-esp8266-breakout/using-arduino-ide
https://www.hackster.io/harshmangukiya/how-to-program-esp8266-with-arduino-uno-efb05f