[QUESTION] How would I make a prison architect style building mechanic?

Hello, I’m curious if anyone can explain or point me towards a tutorial on how I would be able to remake the prison architect building mechanic. If you haven’t played P.A. I’m talking about in the beginning you lay out your plans for the prison by placing walls and rooms in a silhouette mode. When you press play you have workers that build what you had planned. I’d like to remake that in 3D. Can anyone help explain how to do that or point me towards a tutorial? Thanks.