Hi there,
My husband, who was baptized Anglican, received Confirmation/First Communion in the Catholic Church in April of 2012.
It was recommended that he begin living his life as a Roman Catholic when he decided that he wished to become one. He had been attending Mass for several months before joining RCIA in September 2011, and lived all of the canonical requirements to the best of his abilities during his preparation time. We were engaged at the time he was in the process to be married in the Church, so it was a little less complex where martial requirements are concerned.
If a person is becoming Catholic and is already married, they should consult their pastor about having their marriage “Blessed” (ie declared valid in the Catholic Church), or, if they are divorced, obtaining a church anulment if they intend to remarry and/or are remarried. If they are single, they are expected to respect the Church requirements surrounding the state of singlehood (i.e. chastity) until they choose to marry or enter a religious vocation etc. These are things that they should explore and learn about during the RCIA process.
My now-husband basically participated in everything except the Sacraments until right before his Confirmation/First Communion, when he made his First Reconciliation.
God Bless!