Looping through GreyBlocks how I want to loop through

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1

I want to loop through all instantiated GreyBlocks in the scene. Then be able to determine their x,y locations so I can use them in a RectsOverlap function, if there is one, for custom collision.

There is a separate object which is my character which will also be used in the collision check.

How can I do this?

Here is how I instantiate the grey blocks. They are instantiated according to what is stored in the LevelArray.

    for (int x = 0; x < 30; x++)
    {
        for (int y = 0; y < 16; y++)
        {
            if (levelArray[x, y] == 2)
            {
                PackedScene joeScene = (PackedScene)ResourceLoader.Load("res://GameObjects/joe.tscn");
                Joe = (Joe)joeScene.Instantiate();
                Joe.x = x * 64f;
                Joe.y = y * 64f;
                Joe.Position = new Vector2((float)(Joe.x), (float)(Joe.y));
                AddChild(Joe);
            }else if (levelArray[x, y] == 1)
            {
                PackedScene greyBlock = (PackedScene)ResourceLoader.Load("res://GameObjects/grey_block.tscn");
                GreyBlock gb = (GreyBlock)greyBlock.Instantiate();
                gb.x = x * 64f;
                gb.y = y * 64f;
                gb.Position = new Vector2(gb.x, gb.y);
                AddChild(gb);