Q: Is the ANTICHRIST already on the planet earth? If there are more than one, can you mention some of them even the big people in the world?
A: You are asking a question for which I have no answer. The concept of an "antichrist" is not addressed or even mentioned in The Urantia Book. I believe that it is a term which comes from the Bible, and even there, it is mentioned only a few times. But the term itself paints a sinister picture of a being who is the opposite (and possibly equal) of Christ Jesus. There is no such being. There is no evil entity who is the equal and opposite of God...no evil being who is the epitome of badness, as Jesus is the epitome of goodness. Even so-called "devils" were created by God and are under the rule of God.
This is not to say that there are not evil people in this world. There certainly are, but I am in no position to be able to name them for you, nor would I spend my time trying to identify them. Most human beings—even evil ones—are a mix of both good AND evil, but none are equal in power to God, or to Jesus, who was God incarnate.
I am sorry to be of so little help in answering your question. I might suggest that you read more of The Urantia Book, so that you can gain a far more solid grip on the nature of spiritual reality...