Been a CC (Cradle Catholic) for over 50 years now. Will never leave the Church Jesus founded (historical fact) as no other Church is founded on the Apostles, who learned directly from Jesus and the Holy Spirit.
No other church can teach what Mk 16:15-16 means. “Preach the gospel to all creation, he who believes & is baptized will be saved, he who does not will be condemned”. Only the Cath Church both knows what the content of this gospel is & has the authority to teach it & interpret it.
It is the oral word of God which St Peter, St Paul et al preached and which is transmitted from generation to generation by the Pope & bishops in union with him. This oral word of God is distinct from the written word of God, the Scriptures, and is the source of all Church teachings.
When the apostles preached they invited people to come to Jesus in order to be saved (from what?) from their sins in order to be in union with God. “He who commits sin is a slave to sin” and this addiction/slavery to mortal or deadly sin leads to misery, regardless of how much money one has or whether politically free or not.
I received this liberation from sin in baptism and maintain it through the Eucharist, “Unless you eat my body & drink my blood you have no life within you.” Only the Eucharist, in combination with Reconciliation, gives us the grace to remain liberated from serious sin thereby “saving” us, which means to be in union with God so we can serve him and our neighbor in love & joy.
I hope then to maintain this salvation, or union with God, by not commiting any mortal sins or if I do, by repenting of them & confessing them. If I die saved, in union with God on this earth, then I will be united with him forever in heaven after being purified in purgatory.
All of this I know with the certitude of truth because it is what the Apostles preached, the unwritten word of God transmitted in Tradition. It doesn’t come from my or anyone’s personal guesswork on bible verses.