Catholic colleges do not require students to be of the catholic faith in order to attend their school. However, some schools may still require all students to attend things like mass, chapels, or they may require a certain number of religious courses be taken by students. These requirements will depend on the school.
Some catholic colleges may not have any religious obligations for students, and some may have daily religious obligations. Most catholic colleges will encourage participation or attendance at mass or chapel, as is in line with their goal to prepare students and make them more like Christ, but that does not always result in required attendance. Because religious obligations will vary by college, check the website and with the admissions department of the school(s) you are interested in to find out what the expectations are as far as religious obligations.