He doesn't know anything about his parents as of yet and odd things are happening that protect him from things he does not like. After he starts going to Hogwart's he starts learning how to use his gift. He prefers to use brains and not brawn. This is best exemplified at the end of the book when Harry learns Professor Quirrel is the person after the Sorcerer's Stone, which is hidden in The Mirror of Erised. Instead of trying to use physical force against Professor Quirrel, Harry used wit instead. Harry didn't want the stone to use, he only wanted it so Voldemort, who was hiding under Professor Quirrel's turban and had possessed him, couldn't have it.
The protagonist is without a doubt Harry Potter. But it seems that there is more than one antagonist. The Dursley family because all they do is reject Harry as a family member and make Harry's like intolerable. Then there is also Draco Malfoy, Crabbe, and Goyle who just hate Harry for who he is and try to torture him at every possible opportunity. Harry also thinks that Professor Serevus Snape hates him, when actually he is trying to protect him, regardless of how Snape treats Harry in Potions class. The true antagonist is Professor Quirrel, which the reader doesn't learn until the end of the book when Harry finds Quirrel in the chamber where the stone is being kept.
Plot Analysis.
In the opening chapter in the book, Albus Dumbledore and Professor Minerva McGonagall are sitting on a wall at 4 Privet Drive. Soon after, Hagrid joins the two carrying a small bundle, which turns out to be Harry Potter. Hagrid and McGonagall are opposed to leaving Harry with the Dursley's because they are the worst kind of "muggles", meaning not of the magical word. The two are worried that Harry's family will prevent him from attending Hogwart, and they have every right to be. But even so, Harry is left with his aunt and uncle after his parent's death.