Hi DL! It just so happens I am taking a catechism course right now & I am on that chapter which speaks about your question. The paragraph starts off by saying: “Full membership in the Church comes from acceptance of all its beliefs & sacraments & from union with the pope & bishops. The Church has a real, if imperfect, unity with Orthodox Churches & with baptized non-Catholics. It is related to people who believe in God-to the Jews with whom we share the Old Covenant (Testament), to Muslims who profess the faith of Abraham, and to other non-Christian religions. Those who, through no fault of their own, do not have an explicit knowledge of Christ can achieve salvation if they try, assisted by God’s grace, to lead good lives; their salvation comes from Christ even though they do not know him. Those who culpably reject Christ & His Church, however, forfeit eternal life, and in this sense it is true to say that outside the Church there is no salvation (C 836-848)”
This is from the Catechism Handbook