The Eucharist is like a special meal that happens during church. It's when we remember the story of Jesus sharing bread and wine with his friends at the last supper.
During the Eucharist, the priest takes a special bread called the Host and says some prayers over it, asking God to bless it. Then, the priest or a helper called a Eucharistic Minister gives a piece of the Host to each person in the church. It's polite to say "amen" after you receive it to show that you believe in Jesus and what he did for us.
Catholics believe that the Host becomes the body of Jesus and the wine becomes his blood during the Eucharist. This is called transubstantiation. They believe that by eating the Host and drinking the wine, they are joining together with Jesus and remembering how he sacrificed himself for us.
It's an important part of the Catholic faith and is usually done every week during Mass. Remember, even though it might seem strange to eat bread and drink wine, it's a special way to remember Jesus and show your belief in him.