Do I need to add some kind of check before continuing when hopping to other void

Question

I'm new(-ish) to C++, and I'm trying to learn something new every day. Today I'm trying to figure this out.

Do I have to check if Valmis == 1 so it won't continue/return before Realtest() is complete?

This is just an example.

int valmis = 0;

void test::Main()
{
    //just some basic stuff

    do
    {
        if (!strcmp())
        {
            //here too
            float testing = 0;
            printf("Test?  1=do it  Else=Nothing\n");
            scanf(" %f", &testing);

            if (testing == 1)
            {
                Realtest();
                //Realtest needs to be completed before continuing
                if (valmis == 1) //Do I need this or does it continue after RealTest() is complete without this?
                return (somethingmate = true);                                                 
            }
            else
            {
                return (somethingmate = true);
            }
        }

    } while();

    return (somethingmate = false);
}

void test::Realtest()
{
    //doing something here that I need to do before continuing in main/letting somethingmate to become true
    valmis = 1; //do i need this?
}