Here is the full list of all 15 Emily is Away <3 achievements. It takes around 12-15 hours to unlock all of the achievements on Windows.
Complete all major endings
[Redacted]
Farm the Golden Karet
Complete an ending with Emily
Open the website
Open this website
Can you pet the dog?
Complete an ending with Evelyn
Complete Chapter 4
Complete Chapter 3
Complete Chapter 2
Complete Chapter 1