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