clone one interface in another of the same type in c++

I want to make a copy of one object of one specific type of interface with another of the same interface, here i will write 2 class examples and their output.

This is class Vehicle:

#ifndef _VEHICLE_
 #define _VEHICLE_


class Vehicle {
public:
    Vehicle(int a): val(a) {}
    virtual ~Vehicle() {}
    virtual void setVal(int i) = 0;
    virtual int getVal() = 0;
protected:
int val;

};

#endif

This is class Car

 #ifndef _CAR_
 #define _CAR_
#include "Vehicle.h"

class Car : public Vehicle {
public:
    Car(int a) : Vehicle(a) {}
    ~Car() {}
    virtual void setVal(int i);
    virtual int getVal();
};

#endif

The two methods of the class car just return the value and modifies it like the names suggest.

This is the code of the main

    #include <iostream>
    #include "Vehicle.h"
    #include "Car.h"

    using namespace std;

int main()
{
    Vehicle * car1 = new Car(0);
    Vehicle * car2 = new Car(1);
    cout << "val car1 :"<< car1->getVal() << endl; 
    cout << "val car2 :"<< car2->getVal() << endl; 
    car1 = car2; //ATTEMPT TO COPY HERE ************************
    cout << "val car1 :"<< car1->getVal() << endl; 
    cout << "val car2 :"<< car2->getVal() << endl; 
    car2->setVal(6);
    cout << "val car1 :"<< car1->getVal() << endl; 
    cout << "val car2 :"<< car2->getVal() << endl;
    car1->setVal(-1);
    cout << "val car1 :"<< car1->getVal() << endl; 
    cout << "val car2 :"<< car2->getVal() << endl;
    return 0;
}

The output will be:

val car1 :0                                                                                                                                                                                                          
val car2 :1

val car1 :1                                                                                                                                                                                                          
val car2 :1 

val car1 :6                                                                                                                                                                                                          
val car2 :6  

val car1 :-1                                                                                                                                                                                                         
val car2 :-1 

As you can see, there are two different objects of the same interface, but as both objects must be pointers because it is an interface, it´s impossible to make just a copy of the object instead of assign the pointer of the "car2" to the "car1".

My question is if there is any way of doing this, or i just need to make a "clone" method.

thank you for the attention, and sorry if the question is very basic, but i am starting with C++ and some things are a little complicated.