Selecting and Rotating 3 Objects on the Game Screen

Hello, I'm making a game and I want the game to be like the description below.

Select a hexagonal group and turn them clockwise or counterclockwise. If a 3-hexagonal group of the same color occurs, they should be exploded, if not the hexagonal pieces should return to the initial state.

I added 2 C# files. I create a hexagonal grid in one. On the other I am getting the mouse click information.

 void SetUp()
     {
         for (int i = 0; i < width; i++)
         {
             for (int j = 0; j < height; j++)
             {
                 float yPos = j;
                 if(i%2 == 1)
                 {
                     yPos += yOffset;
                 }
 
                
                 GameObject hex = Instantiate(hexagons[hexToUse], new Vector2(i * xOffset, yPos), Quaternion.identity);
                 hex.transform.parent = this.transform;
                 hex.name = "(" + i * xOffset + "," + yPos + ")";
             }
             
         }
     }

 private void OnMouseDown()
     {
         firstTouchPosition = Camera.main.ScreenToWorldPoint(Input.mousePosition);
     }
     private void OnMouseUp()
     {
         finalTouchPosition = Camera.main.ScreenToWorldPoint(Input.mousePosition);
    }

But I couldn't create the algorithm I wanted. I wish you help in this matter.