Bind model to dropdown list

Question

I am trying to bind a model called Makes to a drop-down list. I keep getting the error:

NullReferenceException: Object reference not set to an instance of an object. Yemi_Dealership.Extensions.IEnumerableExtensions.ToSelectListItem(IEnumerable Items) in IEnumerableExtensions.cs, line 20 (sli = new SelectListItem)

public static class IEnumerableExtensions
{
    public static IEnumerable<SelectListItem> ToSelectListItem<T>(this IEnumerable<T> Items)
    {
        List<SelectListItem> List = new();
        SelectListItem sli = new()
        {
            Text = "---Select---",
            Value = "0"
        };
        List.Add(sli);

        foreach (var make in Items)
        {
            sli = new SelectListItem
            {
                Text = Items.GetType().GetProperty("Name").GetValue(Items,null).ToString(),
                Value = Items.GetType().GetProperty("Id").GetValue(Items, null).ToString()
            };

            List.Add(sli);
        }
        return List;
    }
}