This is what is expected of anyone who wishes to call themselves, and truly be, Catholic:
I, N., with firm faith believe and profess each and everything that is contained in the Symbol of faith, namely:
I believe in one God, the Father almighty, maker of heaven and earth, of all things visible and invisible. I believe in one Lord Jesus Christ, the Only Begotten Son of God,
born of the Father before all ages. God from God, Light from Light, true God from true God, begotten, not made, consubstantial with the Father; through him all things were made. For us men and for our salvation he came down from heaven, and by the Holy Spirit was incarnate of the Virgin Mary, and became man. For our sake he was crucified under Pontius Pilate, he suffered death and was buried, and rose again on the third day in accordance with the Scriptures. He ascended into heaven and is seated at the right hand of the Father. He will come again in glory to judge the living and the dead and his kingdom will have no end. I believe in the Holy Spirit, the Lord, the giver of life, who proceeds from the Father and the Son, who with the Father and the Son is adored and glorified, who has spoken through the prophets. I believe in one, holy, catholic and apostolic Church. I confess one baptism for the forgiveness of sins and I look forward to the resurrection of the dead and the life of the world to come. Amen.
With firm faith, I also believe everything contained in the word of God, whether written or handed down in Tradition, which the Church, either by a solemn judgment or by the ordinary and universal Magisterium, sets forth to be believed as divinely revealed.
I also firmly accept and hold each and everything definitively proposed by the Church regarding teaching on faith and morals.
Moreover, I adhere with religious submission of will and intellect to the teachings which either the Roman Pontiff or the College of Bishops enunciate when they exercise their authentic Magisterium, even if they do not intend to proclaim these teachings by a definitive act.
Read this very carefully to avoid the dangers of a heretical or schismatic mindset that becomes a magisterium onto its own. We do not make our own rules nor decide what to believe in. We are the sheep of Christ’s flock and we listen and obey.