"The Most Dangerous Game" is available to read for free on several websites, such as the one listed below. Here is a brief summary.
Rainsford, a famous big-game hunter, falls off his ship and is washed ashore on a seemingly deserted island. He finds a chateau owned by General Zaroff, another hunter who has traveled the world looking for challenge. Zaroff claims to be bored with animals and reveals that he uses the island for hunting humans, since they make a more interesting hunt. Rainsford is appalled and demands to leave; Zaroff instead chooses him for his next hunt. Rainsford uses his considerable knowledge of woodcraft and hunting to evade Zaroff, but Zaroff tracks him down anyway; to his surprise, Zaroff leaves without "finding" him, to prolong the hunt. Rainsford sets traps and kills a dog and Zaroff's servant; in desperation, Rainsford leaps into the ocean rather than be killed. Zaroff, returning to his chateau, finds Rainsford in his bedroom; they fight and Rainsford wins, ending with the classic line: "He had never slept in a better bed, Rainsford decided" (Connell).
Although it would have been helpful if you had mentioned WHICH story you wanted summarized in your question, I can tell from the tags "Rainsford" and "Zaroff" that you mean the short story, "The Most Dangerous Game".
Rainsford is a professional hunter. On his way to a jaguar hunt in the Amazon, he falls off the yacht of a friend and client, Whitney. He swims in the direction where he had heard gunshots earlier and manages to wash up on an island. The next day, he discovers the palatial chateau of a mad Cossack, General Zaroff.
He learns that Zaroff has gotten bored hunting the usual big game animals and has created a very special hunting preserve on this island where he hunts what he calls "the most dangerous game" - human beings.
When Rainsford declines to participate in hunting with Zaroff, the general, who has started to find hunting humans with no woods survival skills boring, gets the "brilliant" idea of hunting Rainsford. If Rainsford survives for three days, the general will deliver him unharmed to the mainland. If the general captures Rainsford, well, his head will join those of his new prey in the library.
Rainsford uses all his knowledge of hunting to elude the general. At the end of the third day, he is being chased through the jungle by the general and his pack of dogs. He jumps from the cliff to escape, and the general assumes his quarry has drowned.
That evening, after a fine dinner, the general goes to his bedroom. He finds Rainsford hiding there and accepts Rainsford's challenge. As the general says, one of them will provide a meal for his guard dogs.
At the end of the story, Rainsford decides that he has never slept in a more comfortable bed.