6 meter gradual raft idea and help

[yck86]

I have 6 meters of stepped foundation, but I do not know how to do it. In the attached project, I created -3 basement floors, one 0 level and one 6 meter level slab in architectural mode. I created the border between them with the slab edge. Is my method correct or incomplete or wrong or -3 basement floors and -1? Should I have created a raft on 2 different floors as a basement floor, I am open to all kinds of comments, criticism and valuable opinions, thank you in advance for your interest, I wish you a good work NOTE: the attached project is not an original project, it is just a prototype project that I made to get ideas from you, because the architectural project has not been completed yet and I have received it. did not arrive, thanks again.