We find ourselves focusing on Celes. After her fall from the Blackjack one year ago today, she has been in a coma and tended to by Cid.
Celes decides to embark on repaying Cid with what she can do, by feeding him some fish. Once you gain control of Celes, re-equip her, then exit the building and go to the southern beach. Here, you’ll have to catch some fish for Cid by walking up to them in the water and examining them to grab them.
There are four kinds, two that are good for him, and two that are bad. Honestly, it doesn’t really matter whether Cid lives or dies (as far as the game goes, okay?), so I’m not going into too much detail here. I just will note that Cid does get more ill by the second, so the odds are against you for keeping him alive. Plus, the series of scenes when he dies is more interesting and deep. I’ll just assume that you unintentionally killed him. To feed him the fish, you’ll have to speak with him back in the house. It can take quite a while for him to die.
Eventually, you’ll enter the house and he’ll be dead, as per the above paragraph. Celes will get really upset and flee the cabin, sobbing.
Later on, she awakens at the beach, and not the "Plutonian shores" mentioned in Edgar Allan Poe’s "The Raven". If you head into the house from earlier, you’ll notice a letter from Cid on the ground. Read it, then go down the staircase near the stove to find a raft. Examine it to head out to sea.