Columbia offers a five-year plan in which you can attend Columbia College for three years and The Fu Foundation School of Engineering and Applied Science for two additional years, graduating with both the B.A. and B.S. degrees. If you are interested in the Combined Plan Program (sometimes known as "3-2"), you should apply to Columbia College.
Another five-year program allows you to complete your four-year B.S. program in The Fu Foundation School of Engineering and Applied Science and then, with an additional year of study in Columbia College, to earn the B.A. degree as well. If you are interested in the "4-1" Program, you should apply to The School of Engineering and Applied Science.