Here is the summary i found on Google. Please summarize it again but don’t make it shorter.
With the advice of Elrond and under the direction of Gandalf, Bilbo and the dwarves take the right path that leads into the mountains. As they climb up out of the valley and the weather gets colder and the terrain more dangerous, Bilbo thinks of the joys of summer back at home. The dwarves are hopeful of reaching the Lonely Mountain by Durin’s Day, but Gandalf is skeptical because he knows that the land they are traveling has become evil and dangerous.
The travelers are caught in a violent thunderstorm that is the work of stone-giants. With their ponies, the expedition seeks shelter and sleep in a cave. Bilbo dreams that a crack opens in the back of the cave; he wakes to find that the crack is real and that the ponies have disappeared through it and Goblins have entered. When the Goblins try to grab Gandalf, he creates a great lightning-like flash in the cave and several Goblins fall dead. The crack closes, and Gandalf disappears.
With whips, the Goblins drive Bilbo and the dwarves to the cavern of the Great Goblin. On the way, they see their ponies, who will be eaten by the Goblins. The Great Goblin interrogates Thorin and accuses the dwarves of being spies, thieves, and murderers. The Goblins discover Thorin’s sword, Orcrist or Goblin-cleaver, which they recognize as an elvish sword that killed many Goblins; they know it as Biter. The Great Goblin is enraged and orders the dwarves sent off to their deaths. Suddenly, the lights go off and the sword Glamdring (also called Foe-hammer or Beater), appears by itself, and runs through the Great Goblin, killing him.
Gandalf’s voice leads the dwarves and Bilbo out of the cavern. The Goblins chase after them until, finally, Thorin and Gandalf turn and, with their swords, kill several of the Goblins. Bilbo, the dwarves, and Gandalf then descend deeper into the Goblin tunnels. Goblins sneak up behind Dori, who is carrying Bilbo; Dori falls and Bilbo hits his head on a rock and loses consciousness.