Is a good practice have all flow in main?

What is better practice in big projects? Have all the flow in the main or functions which call to others functions?

I show better with two examples (in a invented language to be more legible).

Example 1 (all the flow in main):

function menu1
{
    print "Select an option."
    print "1. Cake."
    print "2. Water."
    var option
    read(option)

    if (number == 1)
    {
        return 1; // return cake
    }
}

cake()
{
    print "Select an option."
    ...
}

main()
{
    integer optionSelected = menu1()
    if (optionSelect == 1)
    {
        integer optionSelected2 = cake()
        ...
    }
}

Example 2 (the function has the flow):

function menu1
{
    print "Select an option."
    print "1. Cake."
    print "2. Water."
    var option
    read(option)

    if (number == 1)
    {
        cake();
    }
}

cake()
{
    print "Select an option."
    ...
    menu15()
}

main()
{
    menu1()
}