No. The Majority of Catholic colleges do not require that applicants or students be of the Catholic faith. Catholic colleges welcome students of all ethnic and religious backgrounds to apply. The Catholic faith and beliefs may be built into the curriculum and classes, but students are not expected or pushed to convert if they are not Catholic.
Most Catholic colleges are very inclusive of students of differing religious affiliations and beliefs. However, typically the school will promote its own Catholic faith, religious beliefs, and practices above others. The degree to which a school expects student participation in religious events or classes varies by school, so be sure to check out the College's website to determine if it is the right fit for you.