Here is the full list of all 19 Doki Doki Literature Club Plus! achievements. It takes around 6-8 hours to unlock all of the achievements on Windows.
Achieve 100% data collection.
Listen to a lot of what Monika has to say.
Review Paula's project plan.
Spend 20 minutes listening to music on the desktop.
Finish all of the Side Stories.
Draw boxes on the desktop.
Choose not to quit DDLC.
Find Dan's special note.
Write a perfect poem for Yuri.
Write a poem in 20 seconds or less.
Write a perfect poem for Sayori.
Spend enough time during the poem minigame for the music to loop.
Delete Monika twice while getting deleted zero times.
Love, Monika
Ruin the game.
Write a perfect poem for Monika.
Your desktop wallpaper could not be changed due to an administrative policy restriction on this computer. For more information, contact your system administrator.
Start a New Game.
Write a perfect poem for Natsuki.