How to make such a sidebar on a 3d scene so that it does not hide the scene?

Question

How to make such a settings panel so that you can see the scene with 3d figures as in the picture?
my scene is under the panel. I create a BorderPane, And she completely closes the scene.

My code is in the second picture, but I don’t know how to make the scene visible

 RadioButton rdoEasy = new RadioButton("Easy");
    RadioButton rdoMedium = new RadioButton("Medium");
    RadioButton rdoHard = new RadioButton("Hard");
    var groupDifficulty = new ToggleGroup();
    groupDifficulty.getToggles().addAll(
            rdoEasy,
            rdoMedium,
            rdoHard
    );
    ToolBar toolBar = new ToolBar();
    toolBar.setOrientation(Orientation.VERTICAL);
    toolBar.getItems().addAll(
            new Separator(),
            rdoEasy,
            rdoMedium,
            rdoHard,
            new Separator()
    );
    BorderPane borderPane = new BorderPane();
    borderPane.setLeft(toolBar);
    borderPane.setCenter(group);
    borderPane.getCenter();
    Scene scene = new Scene(borderPane, orgSceneX, orgSceneY,true,SceneAntialiasing.BALANCED);