Here is the full list of all 33 Pixel Puzzles 2: Birds achievements. It takes around 8-10 hours to unlock all of the achievements on Windows.
Complete All Puzzle
Complete Puzzle 25
Complete Puzzle 24
Complete Puzzle 20
Complete Puzzle 11
Complete Puzzle 8
Complete Puzzle 17
Complete Puzzle 14
Complete Puzzle 19
Complete Puzzle 22
Complete Puzzle 21
Complete Puzzle 23
Drob 100 crabs in 1 session
Complete Puzzle 16
Complete Puzzle 18
Complete Puzzle 1
Complete Puzzle 5
Complete Puzzle 15
Complete Puzzle 12
Complete Puzzle 6
Complete Puzzle 13
Complete Puzzle 9
Remove the crabs
Complete Puzzle 10
Complete Puzzle 7
Complete Puzzle 2
Complete Puzzle 4
Use ghost power
Use Rotation power
Complete Puzzle 3
Use location power
Drop a crab in the net
Complete DL-TV Puzzle