If you have already spoken to your parish priest about getting married in a Catholic Church, he will most likely have talked to you about marriage preparation. Some couples do this with other couples in the parish, some are recommended an online course, others will have a series of discussions with just the parish priest. There are also plenty of resources couples can seek out by themselves and do alongside the parish programme. You will find those that the Diocese of Brentwood recommend in the links to courses and books below.