I was Baptized as a protestant. I was not quite an adult, but I was of the age of reason. I do not recall being asked about any particular beliefs. My protestant Baptism was later accepted by the Church, so I never made any such profession.
If there is some list of required beliefs (or even just one single required belief), I ask you to specify and cite it. Even if it is only one.
The Church won’t rebaptise, because a Trinitarian formula baptism is a one time sacrament. Even if done by a non Catholic. But baptism is only a beginning.
Have you not been asked at mass particularly during the Easter season to renew your baptismal promises?
Celebrant: Do you reject Satan?
Response: I do.
Celebrant: And all his works?
Response: I do.
Celebrant: And all his empty promises?
Response: I do.
Celebrant: Do you believe in God, the Father almighty, Creator of heaven and earth?
Response: I do.
Celebrant: Do you believe in Jesus Christ, His only Son, our Lord, Who was born of the Virgin Mary, was crucified, died, and was buried, rose from the dead, and is now seated at the right hand of the Father?
Response: I do.
Celebrant: Do you believe in the Holy Spirit, the holy catholic Church, the communion of saints, the forgiveness of sins, the resurrection of the body, and life everlasting?
Response: I do.
True. But belief is not required. Assent and belief are not the same thing. Assent means we agree that the Church teaches truth, even if we are having a hard time accepting it.
When you are asked do you “believe”, and you say I do, that’s a statement of Faith. Assent to what the Church teaches is an extension of that faith.