The church is often compared to the human body in the Scriptures. The members of the church are represented as the various parts of the body. Christ is always said to be the head. (See 1 Cor. 12:12-27; Eph. 1:22-23; 4:15-16). Question , “What part of the body is the Pope?”
The analogy in question doesn’t necessarily provide an answer to what part any one of us are. Scripture says we are all members of one body with different functions. Paul tells us that we all can’t be an eye because then we could not hear, we all can’t be an ear because then we could not smell. Follow that to the end of the chapter and we see that all are not teachers, and all are not prophets, all do not speak in tongues, all do not have the gift of healing, etc.
So we see the issue is not necessarily just one of Jesus is the head so who is the Pope? He is obviously a teacher, though some have been better than others in that regard. However, the greater message in that chapter of Scripture is that we should look to our own gifts and not the gifts of others. Those who have the gift of teaching should teach, those who have other gifts should use those other gifts.
What is more, when speaking specifically of the Pope and not the Body of Christ as a whole as Paul was here, we see other functions of the office. Jesus says in Luke 22 that Peter, and subsequent Popes, would serve as an anchor securing the faith of others. He prayed that Peter’s faith would not fail and that he could strengthen his brother’s faith. We also see in Scripture that Peter serves an organizational role, he presides over the selection of Mathias to replace Judas, he presides over the Jerusalem Council, he also excommunicates Ananias and Sapphira. These are a few specific examples of Peter exercising his office as bishop and Pope.
You should not be concerned that the Pope’s role is similar to that of Jesus. The Pope is the visible head of the Church. We know that God is the rock, yet Peter is also a rock, we know that is our Father, yet Paul says he is the spiritual father of many. These similar roles are both dependent upon and subordinate to the primary role of God in these regards. Just as you may help bring someone to know Jesus, and yet that is primarily the role of the Holy Spirit.