Modified version of sample code from https://www.arduino.cc/en/Reference/SoftwareSerial

gistfile1.ino

/*
  Software serial multple serial test
 
 Receives from the hardware serial, sends to software serial.
 Receives from software serial, sends to hardware serial.
 
 The circuit: 
 * RX is digital pin 2 (connect to TX of other device)
 * TX is digital pin 3 (connect to RX of other device)
 
 created back in the mists of time
 modified 25 May 2012
 by Tom Igoe
 based on Mikal Hart's example
 
 This example code is in the public domain.
 
 */
#include <SoftwareSerial.h>

#define BAUD_RATE 9600

char tmp;

SoftwareSerial mySerial(2, 3); // RX, TX

void setup()
{
  Serial.begin(BAUD_RATE);
  mySerial.begin(BAUD_RATE);
}

void loop()
{
  if (mySerial.available()) {
    tmp = mySerial.read();
    if (tmp == 13) {
      Serial.write('\n');
    }
    else {
      Serial.write(tmp);
    }
  }
  if (Serial.available()) {
    tmp = Serial.read();
    mySerial.write(tmp);
  }
}