Here is the full list of all 8 You Will (Not) Remain achievements. It takes around 0-1 hour to unlock all of the achievements on Windows.
Drink a whole lot of coffee.
Neglect your plant like you neglect yourself.
Find Lambshank.
Play fetch for the last time.
Spend some time relaxing on the balcony.
Listen to the first radio message.
Interact with the front door after Lambshank drags you away.
Water your plant and water you soul.