Welcome to the Church, Christopher! I’m glad you asked this question, because even many priests and religious educators don’t know the correct answer. St. Christopher is still a saint. What happened in the 1960s was that the Church revised its universal calendar, the schedule of celebrations that are observed by the worldwide Church. Some saints’ days were removed, others added. This did not mean that those removed were no longer saints—only that the Church no longer celebrated their feast days everywhere. Individual communities and Catholics are still free to honor these saints and choose them as patrons. In fact, only a tiny percentage of canonized or recognized saints appear in the universal calendar. Many saints of religious orders are honored only within that order, for example.
You can be proud to have a powerful patron, intercessor, and namesake in St. Christopher. We know little about him historically—only that he died about A.D. 251—but that is also true of many early martyrs. We know they are in heaven, nonetheless.