The Catholic Church teaches that Jesus is truly and substantially present under the appearance of bread and wine in the Eucharist.
It is not a "symbolic" presence, but a true and "real" presence; Jesus is there, as he was when he walked the earth.
This is a difficult teaching for many as it surpasses reason and requires a strong faith and trust in God.
St. Paul VI reflected on this reality in his encyclical Mysterium Fidei.
If Jesus said to his apostles that he is the "bread of life," and that we must "eat" him, we need to trust that Jesus wasn't lying or speaking symbolically.
He truly wanted us to eat the bread that he will give to us.
If you find yourself having difficulty with believing in the Eucharist, then ask God for help. Only he can provide the faith and trust that we need to take Jesus at his word that he is there under the appearance of bread and wine.