Just as the surface ectoderm develops the external structures of the body (e.g. skin, hair, and cutaneous glands), the endoderm develops the structures that line the inside of the body including the urogenital systems, gut tube, and respiratory system
If there is the demand for this, I can publish notes showing the development of each of these separately but a substantial amount of detail is not required for most medical school exams. Please comment below if you would like to have access to this.