Trying to implement a Unity tutorial in Godot with C# (Solved)

Question

Solved:

Instead of using PackedScene[ ], use Array<PackedScene>
[Export] public Array<PackedScene> BottomRooms;
[Export] public Array<PackedScene> TopRooms;
[Export] public Array<PackedScene> LeftRooms;
[Export] public Array<PackedScene> RightRooms;
[Export] public PackedScene ClosedRoom;

---

Trying to implement a Unity tutorial to Godot (Random Dungeon Generator) in C#
Help
Hi.

Trying to implement this tutorial to Godot: https://www.youtube.com/watch?v=qAf9axsyijY I have problems.

// ProceduralLevels.cs
// I've tried with Node2D
[Export] public PackedScene[] BottomRooms;
[Export] public PackedScene[] TopRooms;
[Export] public PackedScene[] LeftRooms;
[Export] public PackedScene[] RightRooms;

And

[Export(PropertyHint.Flags, "Top,Left,Right,Bottom")] public int Pos = 0;

ProceduralLevels levels;
uint randNum;
public bool spawned;
SceneTreeTween tween;
public override void _Ready()
{
    GD.Randomize();
    levels = GetTree().Root.FindNode("Levels", true, false).GetNode<ProceduralLevels>("Levels");
    // levels = FindParent("Levels").GetNode<ProceduralLevels>("Levels");
    Spawn();
}

public override void _Process(float delta)
{
    DetectRooms();
}

public void Spawn()
{
    if (!spawned)
    {
        GD.Print("Spawn");
        if (Pos == 0)
        {
            randNum = GD.Randi() % (uint)levels.BottomRooms.Length;
            GD.Print("Spawn::Bottom: ", randNum);
            AddChild(levels.BottomRooms[randNum].Instance());
        }
        else if (Pos == 1)
        {
            randNum = GD.Randi() % (uint)levels.TopRooms.Length;
            GD.Print("Spawn::Top: ", randNum);
            AddChild(levels.TopRooms[randNum].Instance());
        }
        else if (Pos == 4)
        {
            randNum = GD.Randi() % (uint)levels.LeftRooms.Length;
            GD.Print("Spawn::Left: ", randNum);
            AddChild(levels.LeftRooms[randNum].Instance());
        }
        else if (Pos == 8)
        {
            randNum = GD.Randi() % (uint)levels.RightRooms.Length;
            GD.Print("Spawn::Right: ", randNum);
            AddChild(levels.RightRooms[randNum].Instance());
        }
        spawned = true;
    }
}

void DetectRooms()
{
    if (GetOverlappingAreas().Count == 0) return;
    foreach (Area2D item in GetOverlappingAreas())
    {
        if (item.IsInGroup("SpawnPoint"))
        {
            QueueFree();
        }
    }
}

Also, in the Unity tutorial is using Invoke(); How to implement Invoke in Godot C#?

Thank you.