Работа с объектами классов в односвязном списке

class Student {
public:
    Student(); 
    Student(int a, double ar, const char *str); 
    Student(const Student &obj); 
    void edit();
    virtual void show();
    void summ(Student & obj);
    friend void difference(Student &minuend, Student &subtrahend); 
    friend void Erase(Student &str, int pos, int n); и
    Student & operator++();  
    Student & operator++(int value);  
    operator int() const;
    operator double() const;
    //operator char() const;
    ~Student(); 
 
protected:
    char *surname;
    int age;
    double average_rating;
};
 
class Free_EducationStudent :public Student {
    int stipend;
public:
    Free_EducationStudent();
    Free_EducationStudent(int a, double ar, const char *str, int money); 
    Free_EducationStudent(const Free_EducationStudent &obj);
    void show();
    ~Free_EducationStudent();
};
 
class Paid_EducationStudent :public Student {
    int CostEducation;
public:
    Paid_EducationStudent();
    Paid_EducationStudent(int a, double ar, const char *str, int money); 
    Paid_EducationStudent(const Paid_EducationStudent &obj);
    void show();
    ~Paid_EducationStudent();
};
template<class T>
class List
{
public:
 
    List();
    ~List();
 
    //добавление элемента в конец списка
    void push_back(T data) {
        if (head == nullptr)
        {
            head = new Node<T>(data);
        }
        else
        {
            Node<T> *current = this->head;
 
            while (current->pNext != nullptr)
            {
                current = current->pNext;
            }
            current->pNext = new Node<T>(data);
 
        }
 
        Size++;
    }
 
    // получить количество элементов в списке
    int GetSize() { return Size; }
 
    T& operator[](const int index);
 
private:
 
    template<class T>
    class Node
    {
    public:
        Node * pNext;
        T data;
        
        Node(T data = T(), Node *pNext = nullptr)
        {
            this->data = data;
            this->pNext = pNext;
        }
    };
    int Size;
    Node<T> *head;
};