Add object OnMouseDown

I’ve been searching for answers here in the unity community but I couldn’t, it’s been frustrating me for a month now.
So I’m trying to make a farming simulation game like harvest moon or Stardew Valley, I have a plot, and whenever I want to do something (let’s say OnMouseDown), I would like to add an object (this object is a seed and has childrens which later on will turn to plant and fruit), now I’m doing the gameoject.setactive like i did on image 2, but that’s not what I want since there would be a multiple plots. I was thinking of snapping it to the center of plot OnMouseDown but I don’t know where to start. Can someone please give me any idea? answer would be much much appreciated!

What if you just instantiated it?

void OnMouseDown()
{
    Instaniate(seedPrefab, desiredPosition, Quaternion.identity, if you want to parent the object, insert parent transform here)
}

Then on the seed prefab do some kind of

void Start()
{
    GrowthSimulation();
}