Here is the full list of all 30 Hope Lake achievements. It takes around 3-4 hours to unlock all of the achievements on Windows.
Animals puzzle completed
Stopped Peter and saved Emily!
Identified the mystery person
All photos found
All evidence collected
The dragon defeated
Escaped the trap
You got a revolver
Emily is awaken!
Mystery of the painting solved
Telescope puzzle completed
All special keys found
Got out of the dead end
Piano keys found
Courtyard reached
Record found
Coffin lid lifted
Mix puzzle completed
Books puzzle completed
Hex tile found
The fire is put out
Sliding puzzle completed
Get into boarding school
Pipes puzzle completed
Disc puzzle completed
Case a lion head
Got the Valve :)
Took the flashlight
Handkerchief evidence found
Gas up the car