Short answers, pulled from the story.
Paris is a Trojan prince, son of King Priam and Queen Hecuba, and younger brother of Prince Hector. His elopement with Helen of Sparta triggered the Trojan War. He later killed Achilles with an arrow, aided by Apollo.
The Judgement of Paris was a divine contest in which Paris selected Aphrodite as the most beautiful goddess, passing over Hera and Athena. The dispute began when Eris threw a golden apple inscribed 'For the most beautiful' into the wedding feast of Peleus and Thetis, and Zeus refused to decide the outcome himself. Aphrodite's bribe was the love of Helen of Sparta.
Homer's Iliad describes Paris as a reluctant warrior who preferred the bow to close combat, a preference that set him apart from the heroic code followed by fighters like Hector. He wounded Diomedes through the foot in Book 11 of the Iliad, and his injury of the healer Machaon shifted the battle in Troy's favor. In the Aethiopis, he kills Achilles with an arrow, with Apollo's assistance.
Paris was mortally wounded by Philoctetes in a duel late in the Trojan War. He sought healing from Oenone, a nymph who had been taught medicine by Apollo and had promised she could cure any wound, but she refused him. Paris died that same day, either in Troy or on the slopes of Mount Ida.
Oenone was a nymph from Mount Ida in Phrygia and Paris's first lover, before he left her for Helen of Sparta. Her father was the river-god Cebren, and she had been taught prophecy by Rhea and medicine by Apollo. She foresaw Paris leaving her, told him to return if wounded, and refused to heal him when he did.
Orlando Bloom played Paris in the 2004 Hollywood film Troy. The character is portrayed as an irresponsible prince who chose romance over family and country, and in that version, Paris survives the fall of Troy by escaping with Helen.