What are some Catholic religious traditions and beliefs?
There are several resources available (online and elsewhere) for a basic search of the history and beliefs of the Roman Catholic church (starting with the link below) to help you get started on this assignment, but I imagine it would also be helpful for you to seek answers and suggestions from actual members of the Catholic church.
I can speak from personal experience because I grew up in the Roman Catholic church and attended Catholic school until 8th grade. In short, the Catholic church is very traditional and liturgical in its beliefs and practices. Like the protestant churches, the foundation of the Catholic faith is the belief in Jesus Christ as the son of God, who died on the cross to take away the sin of the world. Catholics come together for worship traditionally once a week, on Sundays, and celebrate mass. Mass, in most Catholic churches, lasts one hour, and follows a specific liturgy, including readings from the Old and New Testaments, corporate prayer, the singing of hymns or worship songs, and participation in communion. Unlike Protestants, Catholics believe in transubstantiation, which means that when the priest blesses the sacrament (the bread and the wine), they become the actual body and blood of Christ. Protestants take communion as a symbolic gesture of remembrance only.
Traditionally speaking, the Catholic church is governed very strictly and there is absolute order in leadership. The head of the Catholic church is the pope, who is elected and lives in The Vatican. Under the pope are cardinals, then bishops, then priests, then deacons. Catholics traditionally ordain only men into such leadership positions, and these men take a vow of celibacy and do not marry.
Though there are many traditions in the Catholic church, most average Catholic families participate or observe the following as the most important: Christmas Eve or Christmas Day mass, Easter Vigil service and Easter Sunday Mass, baptism of babies (by sprinkling), 1st communion of children, partaking in communion at Mass, confession and reconciliation, and marriage within the Catholic church. Other Catholic beliefs and traditions include praying to the saints (including Mary, the mother of Jesus) with specific requests, charitable acts to the sick and the poor, and penance for sin, which is often suggested by a person's priest and includes actions and prayer which show repentance and the acceptance of God's grace and forgiveness.