平步, 平 = flat so it is easy and safe to walk on vs a slope. 步 = walk. In Chinese, most nouns can be verbs and vice versa. 青雲 = blue clouds. So it figuratively means "reaching the heights of heaven". This came from the Annals of History 史記, about a minister who uttered that if he does not remonstrate, how could he be beyond the blue clouds.