Generating Chunks

Hello, so i have finaly managed to generate chunks with a lot of help from this great community. So i want to generate only visible block for now, but i am stucked at there how to manage thath, i have now only chunks and 1 block generated, here is my code:

ChunkData.cs

 public class ChunkData
 {
     private int x, y, z;
 
     public ChunkData(int _x, int _y, int _z)
     {
         x = _x;
         y = _y;
         z = _z;
     }
 
     public int X
     {
         get { return x; }
         set { x = value; }
     }
 
     public int Y
     {
         get { return y; }
         set { y = value; }
     }
 
     public int Z
     {
         get { return z; }
     }
 
     public override string ToString()
     {
         return string.Format("Chunk ( {0},{1},{2} )", x, y, z);
     }
 }

WorldData.cs

 public class WorldData
 {
     private int chunkWidth = 32, chunkHeight = 128, chunkDepth = 32;
     private int chunksX = 8, chunksY = 1, chunksZ = 1;
 
     public ChunkData[, ,] chunks;
 
     public const int BottomChunkBorderRow = 0, LeftChunkBorderColumn = 0;
 
     public void InitChunkGrid()
     {
         chunks = new ChunkData[chunksX, chunksY, chunksZ];
 
         for (int x = LeftChunkBorderColumn; x <= RightChunkBorderColumn; x++)
         {
             for (int y = BottomChunkBorderRow; y <= TopChunkBorderRow; y++)
             {
                 for (int z = 0; z < chunksZ; z++)
                 {
                     chunks[x, y, z] = new ChunkData(x, y, z);
                 }
             }
         }
     }
 
     public int ChunkWidth
     {
         get { return chunkWidth; }
         set { chunkWidth = value; }
     }
 
     public int ChunkHeight
     {
         get { return chunkHeight; }
         set { chunkHeight = value; }
     }
 
     public int ChunkDepth
     {
         get { return chunkDepth; }
         set { chunkDepth = value; }
     }
 
     public int ChunksX
     {
         get { return chunksX; }
         set { chunksX = value; }
     }
 
     public int ChunksY
     {
         get { return chunksY; }
         set { chunksY = value; }
     }
 
     public int ChunksZ
     {
         get { return chunksZ; }
         set { chunksZ = value; }
     }
 
     public int TopChunkBorderRow
     {
         get { return chunksY - 1; }
     }
 
     public int RightChunkBorderColumn
     {
         get { return chunksX - 1; }
     }
 }

WorldGameObject.cs

 public class WorldGameObject : MonoBehaviour 
 {
     private WorldData world = new WorldData();
 
     public Transform chunkPrefab;
     public Transform[, ,] chunkGO;
 
     void Start()
     {
         world.InitChunkGrid();
 
         CreateChunks();
     }
 
     private void CreateChunks()
     {
         chunkGO = new Transform[world.ChunksX, world.ChunksY, world.ChunksZ];
 
         for (int x = 0; x < world.ChunksX; x++)
         {
             for (int y = 0; y < world.ChunksY; y++)
             {
                 for (int z = 0; z < world.ChunksZ; z++)
                 {
                     ChunkData curChunk = world.chunks[x, y, z];
 
                     Vector3 chunkInstPos = new Vector3(curChunk.X * world.ChunkWidth, 0, curChunk.Y * world.ChunkHeight);
 
                     Transform chunkInst = Instantiate(chunkPrefab, chunkInstPos, Quaternion.identity) as Transform;
 
                     chunkInst.parent = transform;
 
                     chunkInst.name = curChunk.ToString();
 
                     chunkGO[x, y, z] = chunkInst;
                 }
             }
         }
     }
 }

So i have created new empty game object called World Spawn and attached WorldGameObject to it, and attached Grass prefab (Cube with grass texture). Now it generates only 1 block in chunk. So my question is how i can generate more blocks in these chunks and if possible thath i generate only visible blocks.