How to add a string to a List

I have a variable usersInput which has a value Console.ReadLine()
I want to add this variable to the array built with List

static void Resize<T>(ref List<T> array, string name)
        {
                     
            array.Add(name);
            Console.WriteLine();
            for (int i = 0; i < array.Count; i++)
            {
                Console.WriteLine(array[i]);
            }
        }


static void Main(string[] args)
        {

             List<string> teachers = new List<string> { "1", "2", "3"};
             Console.WriteLine("Enter a name");
             string userInput = Console.ReadLine();
             Resize(ref teachers, userInput);
                           
        }

>Solution :

Why do you need Resize<T> method at all? You could do it easier:

    static void Main(string[] args)
    {

        List<string> teachers = new List<string> { "1", "2", "3" };
        Console.WriteLine("Enter a name");
        string userInput = Console.ReadLine();

        if (string.IsNullOrWhiteSpace(userInput) || !string.IsNullOrEmpty(userInput))
        {
            teachers.Add(userInput);
        }

        // if want to change list to array then use
        // var arr = teachers.ToArray();

        foreach (var teacher in teachers)
        {
            Console.WriteLine(teacher);
        }

    }