How to generate building on surface I have created 20 towers.

Each tower contains few mesh. Each tower is not with single mesh. Some are curve some have array modifiers some bevel etc.
I want to generate on a plane to make a city. With single mesh we can. I have created collection to divide the building small medium and large.

I have created a generation result collection and in that 3 collection (small medium and large).
In the small medium and large collection i have divide the collection in the name s1 s2 for each building.
I tried to parent each building with the base of plane. But all mess. All the parts of the building distributed here and there.
Any solution how can i fix all the building on single plan to make a city. Thanks
I'm guessing here, but it seems you have buildings made with separate meshes and want to place each building as a complete whole, onto the plane?
If so you can make each building's component a &quot;Child&quot; of a parent, which could be an Empty.  You then move that empty onto the plane and all of the building's components will stick together and follow.
You do the same for each building.
Once each (building) is on the plane, the plane itself can then act as a parent for all of the building-parents, i.e. make a city block which will stick together should you move the plane.
See this answer here -
Partial Rotation
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