I am non-denominational. I have a couple Catholic friends and one of them told me that the Pope is God. Remembering what I heard about the Catholic religion, I corrected him and said that he was at most merely God's representative, and at least a fellow believer. My friend told me again the Pope is God, so this made me slightly confused. As I remember, Catholics believe the Pope is just God's representative on Earth. Am I wrong?
Your friend is confused. Very confused. The Pope is not God according to any official Catholic teaching.
Catholics believe a lot of things about the Pope including his ability so speak infallibly (see ex cathedra) and that his role is that of an authoritative representative of God (see vicar of Christ). They believe a lot of things about the Pope that Protestants and others disagree with, but they do not believe he is God. Official doctrinal statements do not include such a thing and historically they never have.
The pope is not God, and the Catholic Church does not teach that he is, only that he represents God on earth. However, your friend may have learnt this from the history of Pope Alexander VI, arguably one of the worst of the popes. Russel Chamberlin, in The Bad Popes, page 173, says that at his coronation, Pope Alexander VI (Rodrigo Borgio) committed the blasphemy of having triumphal arches proclaim: "Rome was great under Caesar but even greater far under Alexander. The first was only a mortal – the second is a God."
“To make war against the Pope is to make war against God, seeing the Pope is God, and God is the Pope.” -Moreri's History. (Louis Moréri (25 March 1643 – 10 July 1680) was a French priest and encyclopedist.)
"The leader of the Catholic church is defined by the faith as the Vicar of Jesus Christ (and is accepted as such by believers). The Pope is considered the man on earth who takes the place of the Second Person of the omnipotent God of the Trinity." (John Paul II, Crossing the Threshold of Hope, p. 3, 1994).
"The Pope is not simply the representative of Jesus Christ. On the contrary, he is Jesus Christ Himself, under the veil of the flesh, and who by means of a being common to humanity continues His ministry amongst men ... Does the Pope speak? It is Jesus Christ Who is speaking. Does he teach? It is Jesus Christ Who teaches. Does he confer grace or pronounce an anathema? It is Jesus Christ Himself Who is pronouncing the anathema and conferring the grace. Hence consequently, when one speaks of the Pope, it is not necessary to examine, but to obey: there must be no limiting the bounds of the command, in order to suit the purpose of the individual whose obedience is demanded: there must be no caviling at the declared will of the Pope, and so invest it with quite another than that which he has put upon it: no preconceived opinions must be brought to bear upon it: no rights must be set up against the rights of the Holy Father to teach and command; his decisions are not to be criticized, or his ordinances disputed. Therefore by Divine ordination, all, no matter how august the person may be — whether he wear a crown or be invested with the purple, or be clothed in the sacred vestments: all must be subject to Him Who has had all things put under Him." -Evangelical Christendom, January 1, 1895, pg. 15, published in London by J. S. Phillips.