How could I implement the tree correctly using XAML?

    public new TreeViewItem ToTreeViewItem()
    {
        var treeViewItem = base.ToTreeViewItem();

        treeViewItem.Items.Add(new TreeViewItem {Header = $"Atomic Chunk Count: {AtomicChunkCount}"});
        treeViewItem.Items.Add(new TreeViewItem {Header = $"Light Chunk Count: {LightChunkCount}"});
        treeViewItem.Items.Add(new TreeViewItem {Header = $"Camera Chunk Count: {CameraChunkCount}"});

        return treeViewItem;
    }