Here is the full list of all 38 Castaway Paradise Complete Edition achievements.
Donate all shells
Donated every collectable
Remove 25 cobwebs
Make a profit of 5000 gems on the Stock Market
Donate 15 shells
Make a profit of 2000 gems at the Bank
Grow every type of fruit
Grow every type of flower
Grow every type of crop
Donate all fish
Remove 50 weeds
Donate 15 fish
Rebuild the Lighthouse
Live the luxury life of a VIP
Rebuild Victoria's Mansion
Read 50 chit chats
Rebuild Francis' Pirateshack
Rebuild Amelia's Planehouse
Completed 100 quests
Unlocked a gate
Collect 25 pieces of garbage
Rebuild Angus' Trailer
Donate all bugs
Donate 15 bugs
Donate a collectable
Rebuild Harold's Museum
Rebuild a bridge
Completed 25 quests
Harvest 50 crops
Make a profit of 500 gems on the Stock Market
Used every piece of equipment
Rebuild Gustave's Bakery
Wore an outfit of the opposite gender
Changed every piece of outfit
Unlock the second room in your house
Remove 25 stones
Get your first collectable
Completed the tutorial