/////////////////////
//    Libraries    //
/////////////////////
#include <SPI.h>
#include <Wire.h>

#include <mcp2515.h> // https://github.com/autowp/arduino-mcp2515 + https://github.com/watterott/Arduino-Libs/tree/master/digitalWriteFast

/////////////////////
//  Configuration  //
/////////////////////

#define CS_PIN_CAN0 17

#define SERIAL_SPEED 115200
#define CAN_SPEED CAN_125KBPS // Entertainment CAN bus - Low speed
#define CAN_FREQ MCP_16MHZ // Switch to 8MHZ if you have a 8Mhz module

////////////////////
// Initialization //
////////////////////

MCP2515 CAN0(CS_PIN_CAN0); // CAN-BUS Shield N°1

////////////////////
//   Variables    //
////////////////////


String LeftTemp;
String RightTemp;

// CAN-BUS Messages
struct can_frame canMsgRcv;

void setup() {

    // Initalize Serial for debug
    Serial.begin(SERIAL_SPEED);

    // CAN-BUS from car
    Serial.print("Initialization CAN0");
    
  CAN0.reset();
  CAN0.setBitrate(CAN_SPEED, CAN_FREQ);
  while (CAN0.setNormalMode() != MCP2515::ERROR_OK) {
    delay(100);
  }
}

void loop() {

  // Receive CAN messages from the car
  if (CAN0.readMessage( & canMsgRcv) == MCP2515::ERROR_OK) {
    int id = canMsgRcv.can_id;
    int len = canMsgRcv.can_dlc;

    if (id == 464){

     char tmp[3];

        snprintf(tmp, 3, "%02X", canMsgRcv.data[5]);
        LeftTemp = String (tmp);
        Serial.print("LeftTemp = ");  
        Serial.println(LeftTemp);
        Serial.println(tmp);       

        snprintf(tmp, 3, "%02X", canMsgRcv.data[6]);       
        RightTemp = String (tmp);
        Serial.print("RightTemp = ");        
        Serial.println(RightTemp);
        Serial.println(tmp);    

       Serial.println();
    }

   } 
}

#include "driver/gpio.h"
#include "driver/twai.h"

//#define ACCEPT_ID                  0x036   //11 bit standard format ID;if not define any ID,accept all IDs.

#ifdef ACCEPT_ID
#define MASK_ID                  ~(0x7FF << 21)   //32 bit standard format ID,but only care for the frist 11 bits.
#define TWAI_FILTER_CONFIG() {.acceptance_code = (ACCEPT_ID << 21),.acceptance_mask = MASK_ID,.single_filter = true};
#endif

// Pins used to connect to CAN bus transceiver:
#define RX_PIN 2
#define TX_PIN 1

// Intervall:
#define POLLING_RATE_MS 10


void setup() {
  // put your setup code here, to run once:
  delay (5000);
  Serial.begin(115200);
  twai_init();
}

void loop() {
  // put your main code here, to run repeatedly:
  twai_receive();
}



void twai_init()
{
  //Initialize configuration structures using macro initializers
  twai_general_config_t g_config = TWAI_GENERAL_CONFIG_DEFAULT((gpio_num_t)TX_PIN, (gpio_num_t)RX_PIN, TWAI_MODE_NORMAL);
  //twai_general_config_t g_config = TWAI_GENERAL_CONFIG_DEFAULT((gpio_num_t)TX_PIN, (gpio_num_t)RX_PIN, TWAI_MODE_LISTEN_ONLY);
  twai_timing_config_t t_config = TWAI_TIMING_CONFIG_125KBITS();
#ifdef ACCEPT_ID
  twai_filter_config_t f_config = TWAI_FILTER_CONFIG();
#else
  twai_filter_config_t f_config = TWAI_FILTER_CONFIG_ACCEPT_ALL();
#endif

  //Install TWAI driver
  if (twai_driver_install(&g_config, &t_config, &f_config) == ESP_OK) {
    Serial.println("Driver installed");
  } else {
    Serial.println("Failed to install driver");
    return;
  }

  //Start TWAI driver
  if (twai_start() == ESP_OK) {
    Serial.println("Driver started");
  } else {
    Serial.println("Failed to start driver");
    return;
  }
}

void twai_receive()
{
  //Wait for message to be received
  twai_message_t message;
  if (twai_receive(&message, pdMS_TO_TICKS(POLLING_RATE_MS)) == ESP_OK) {
    //    Serial.println("Message received");
    Serial.println("ID DATA----------->");
    Serial.print(message.identifier, HEX);
    if (!(message.rtr))
    {
      for (int i = 0; i < message.data_length_code; i++)
      {
        Serial.print(" ");
        Serial.print(message.data[i], HEX);
      }
    }
    Serial.println(" ");
  } else {
    Serial.println("Failed to receive message");
    return;
  }
}

Compilation OK

#include <SoftwareSerial.h>

SoftwareSerial mySerial(2, 1); // RX, TX

void setup()
{
  delay (5000);
  // Open serial communications and wait for port to open:
  Serial.begin(9600);
  while (!Serial) {
    ; // wait for serial port to connect. Needed for Native USB only
  }

  Serial.println("Goodnight moon!");

  // set the data rate for the SoftwareSerial port
  mySerial.begin(9600);
  mySerial.println("Hello, world?");
}

void loop() // run over and over
{
  if (mySerial.available())
    Serial.write(mySerial.read());
  if (Serial.available())
    mySerial.write(Serial.read());
}