Answer:
In the Catholic Church priests and clerics have the authority to forgive people's sins through confession, in Islam only sins are forgiven by Allah
In the Catholic Church they believe in the trinity, in Islam there is a belief in unity.
In the Catholic Church only the bible is accepted as an authentic book, in Islam the Koran is accepted as a book based on revelation.
In the catholic church the words of Jesus are considered the word of God, in Islam the revelation is given by the angel Gabriel.
In the Catholic Church it is believed that man is a sinner by birth and must be baptized to be cleansed, in Islam it is believed that people are born free from sin and that no one should bear the guilt of another.
In the Catholic Church it is believed that Jesus was crucified, in Islam it is believed that Jesus ascended to heaven in the presence of Allah.