Best practice when working between Revit and UE - multiple objects that actually represent one thing

Thanks @pp_rfrost and @pbdarcey

I already use Datasmith and this is exactly how I got all those meshes in.
Let me rephrase my problem. I would like to group multiple items that I want to treat as one single entity. Something tells me grouping is not the way to work in Unreal.

When I export them from Revit, they come of course as single items. I could import to Max, join and re-export. I have a feeling this is not the right way. So I am asking about the best practice in this case. There might be multiple ways, and I’d love to hear your opinions. In a course in the Unreal Online Learning portal, there was something like Blueprint Class > Actor. Is that relevant in my case?

Please see the attached screenshot that I hope will clarify my question and intent.
As you can see from the selection, I don’t want to be able to select each single plank. I might want to join all the planks into one single item, or maybe the roof is one single item.