Here is the full list of all 25 Unpacking achievements. It takes around 3-4 hours to unlock all of the achievements on Windows.
Unpacked 2018.
Built a tower out of baby blocks.
Flushed every toilet.
Unpacked 2015.
Put the tiger and pig side by side.
Found a place for every plant.
Unpacked 2013.
Set the time on the microwave.
Wrote an equation with fridge magnets.
Unpacked 2012.
Rescued a forgotten poster.
Unpacked 2010.
Tidied up his underwear drawer.
Placed all the coffee-making equipment on the counter.
Found a head to wear the hat.
Turned on a game console.
Unpacked 2007.
Made the mannequin dab.
Turned on a music player.
Solved the cube.
Unpacked 2004.
Put an electronic item somewhere dangerous.
Put the cookie jar out of reach.
Unpacked 1997.
Found your camera.