Making random map, how to do this well?

I’m actually making a “Isaac-like”. I made a script who load all the map in my prefabs and then instantiate them with a procedural generation. I think this part is ok. But my problem come from prefabs. In each Map I load, there are various amount of bushes (the bushes are childs prefab of the “Map”). I have actually 20 maps like that. I just changed the sprite of the bush, the original prefab changed, but not every ones in the maps prefabs.
I would like to know how to link the bushes which are in the Map to the original prefab.
And i would like to know if there are better way to do this. My maps is made of a grid so maybe it would be easier (or better) for the game to put the informations in a document the game will load? but i really don’t know how to do this. If it’s more convenient to do this, do you have some ressources about this?

If you don’t understand me clearly, don’t hesitate to ask me more details.

Thanks in advance

Why not trying to serialize your maps. So your maps will not be prefabs anymore. You will just have to do one prefabs for each game object that can be in your map like the bush and so all your bushes will be connected because coming from the same prefab.

You will need a script to save and load maps though.