How to make the compiler 'paste' specific code to an area

i was working on an educationary project to study C++ where specific labels include code to that specific topic being studied. However, at the end of each code block i want the compiler to ask if the user wants to exit or countine from beginning:

        void main(void)
    {
        beginning:
        printf("goto : \n 1) pointers \n 2) classes \n 3) \n 4) \n 5) \n ");
        scanf_s("%d", &input);
            switch (input)
            {
            case 1:
                goto pointers;
            case 2:
                goto classes;
            case 3:
                case 4:
                    case 5:
            default:
                printf("wrong try again \n"); 
                goto beginning;
            }
    pointers:
    .....
    classes:
    ......
}

the code to check what the user wants:

    do {
        printf("1 for exit and 2 for return menu \n");
        scanf_s("%d", &reserved);
        if (reserved == 2) { goto beginning; }
        else if (reserved == 1) { exit; }
        else { printf("wrong number, put a valid one you little..!"); }
    } while (reserved != 1 && reserved != 2);

i tried to turn it to a function but the problem is labels are defined putside of main function so i want to just make the compiler put my function once it is called and not evaulate it from the beginning.