Yeah the question is too vague and the example games you gave are RTS which tend to have the same maps each time as campaigns so you would have set levels and not sure how that relates. What you are describing with the layouts though isn't possible, you don't create them dynamically during run time. You would have one layout for the level, and each time load the level you want, there is no need to create further layouts. If you're referring to random generation of terrain you use arrays and load the levels from them but it gets a bit complex unless you're using a tilemap. There should be some posts around the forum about that kind of thing.