public async void f()
{
       foreach (var item in childrenANDparents)
                {
                 await Task.Run(() => SendUpdatedSiteInfo(item.Host,site_fr));
// foreach loop does not work until the task return and continues
                    }
}

public async void f()
        {
               foreach (var item in childrenANDparents)
                        {
                       Thread t = new Thread(() => SendUpdatedSiteInfo(item.Host, site_fr));
                t.Start();
    // foreach loop  works regardless of the method, in debug mode it shows me
// they are working in parallel
                        }
        }