Here is the full list of all 16 Pineapple on pizza achievements. It takes around 0-1 hour to unlock all of the achievements on Windows.
Get out of the island.
Activate the volcano.
Approach the bench.
Approach the baby.
Ruin the limbo.
Jump from the cliff.
Approach the cliff.
Approach the statue.
Step inside the circle.
Approach the kids playing.
Approach the turtle.
Approach the skilled dancer.
Approach the man feeding the birds.
Walk through the corn plantations.
Step onto a sailboat.
Play.