How to display the largest and the smallest elements of binary tree?

public Node findmin(Node Root)
        {
            if (Root == null)
                return null;
            else if (Root.leftChild == null)
                return Root;
            else
                return findmin(Root.leftChild);
        }

        public Node findmax(Node Root)
        {
            if (Root == null)
                return null;
            else if (Root.rightChild == null)
                return Root;
            else
                return findmax(Root.rightChild);
        }
        
    }

    class Program
    {
            Console.WriteLine("Extreme elements");
            Console.WriteLine("----------------------------------------------------------------");
            Console.WriteLine();
            Console.WriteLine("The smallest element is:");
            //I don't know how to display the smallest or the largest element
             
            Console.WriteLine();
            Console.WriteLine("The largest element is:");

            
            Console.WriteLine();
            Console.WriteLine("----------------------------------------------------------------");

            Console.ReadLine();

        }

    }
}