Jesus gave holy orders to the Apostles. Every bishop in the Catholic Church got holy orders from another bishop in Apostolic succession. All priests got holy orders from a bishop. This is an unbroken chain lasting 2000 years. This Apostolic succession is where the authority of the Pope, bishops and priests get their authority to administer the sacraments, including reconciliation.
God is sufficient!
That is your opinion, and you are entitled to it.
But Catholics believe God did not just toss down a Bible 2000 years ago and leave the world. Christ founded a Church, an institution of men, which is guided in its decisions by the Holy Spirit. The Catholic Church is the only religion in the world with a centralized authority that has lasted for longer than any nation on Earth. It is has survived Roman Emperors, Communist dictators, and the Nazis. It will also survive modern secularism, which seeks to undermine it from within.