If I understand, you are showing an elevation / section of the massing that you want?
Walls can span multiple stories, and the Floor Plan Cut Plane can be used to view horizontal sections of the building at any height.
It seems to me that you might have at most 5 'stories' here. Certainly 3 for providing base heights of the colored modules. But, it seems that what I identify in the screenshot as '1' (sorry 0 in Europe!) is the main floor, 2 is the base floor of the orange module, 3 is the second floor of the orange module, 4 is the base floor for green, and 5 is the main floor for green?
You can build all of this in one file of course, and it does not even require complex profiles - just walls, slabs and "roofs". But, if you want to play with the positioning of these modules relative to each other, then, yes, you can model separately. Model each of the red, orange and green in separate files and Hotlink them into a master file at the appropriate stories.
(But, I may not really understand what you want to do. While English is the official language of this forum, you can post in your native language (French?) as long as you also post an English translation. That might help get a better response from someone who speaks your language.)
Cheers,
Karl
One of the forum moderators
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