<UserControl 
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
    mc:Ignorable="d"
    Height="768" Width="1024" MinHeight="720" MinWidth="1024"
>
    <Grid>
         <ListBox x:Name="MyList" FontSize="24" Height="500" Width="300" />
    </Grid>    
</UserControl>

using Noesis;
using System.Collections.Generic;
using UnityEngine;

public class TestMyList : MonoBehaviour
{
    public int amt = 10;

    private void Start()
    {
        var gui = GetComponent<NoesisGUIPanel>();
        var root = gui.GetContent();
        var MyList = root.FindName<ListBox>("MyList");

        List<string> myStrings = new List<string>(amt);
        string text = "My String #";
        for (int i = 0; i < amt; i++)
        {
             myStrings.Add(string.Concat(text, i));
        }

        MyList.ItemsSource = myStrings;
    }
}