Для вопроса

/*

member initializer 'DataType' does not name a non-static data member or base class
        TypeInfo(PT1 Pvalue1, PT2 Pvalue2) : DataType(Pvalue1, Pvalue2)

use of undeclared identifier 'value1'
                std::cout << "Тип данных значения " << value1 << " - " << typeid(value1).name()

*/


#include <iostream>
#include <string>
#include <fstream>



template<typename T1, typename T2>
class DataType
{

public:
    DataType(T1 value1, T2 value2)
    {
        this->value1 = value1;
        this->value2 = value2;
    }

    void DataTypeSize()
    {
        std::cout << "Значение " << value1 << " занимает " << sizeof(value1) << " байта" << std::endl;
        std::cout << "Значение " << value2 << " занимает " << sizeof(value2) << " байта" << std::endl;
    }


protected:
    T1 value1;
    T2 value2;

};


template<typename PT1, typename PT2>
class TypeInfo : public DataType<PT1, PT2>
{
public:

    TypeInfo(PT1 Pvalue1, PT2 Pvalue2) : DataType(Pvalue1, Pvalue2)
    {

    }

    void ShowTypeName()
    {
        std::cout << "Тип данных значения " << value1 << " - " << typeid(value1).name()
        std::cout << "Тип данных значения " << value2 << " - " << typeid(value2).name()
    }

};



int main(int argc, char *argv[])
{
    setlocale(LC_ALL, "Rus");
    srand(time(NULL));


    TypeInfo<int, std::string> dt(5.99, "пять");

    dt.DataTypeSize();
    dt.ShowTypeName();

    return 0;
}