Here is the full list of all 28 STEINS;GATE 0 achievements. It takes around 35-40 hours to unlock all of the achievements on Windows.
Cleared "Pandora's Box".
Saw 75% of CG.
Cleared "X-Day Protocol".
Cleared "Promised Rinascimento".
Opened Movie Library.
Opened Sound Library.
Opened CG Library.
Opened Clear List.
Cleared "Recursive Mother Goose".
Saw 50% of CG.
Cleared "Antinomic Dual".
Cleared "Twin Automata".
Cleared "The Orbital Eclipse".
Saw 25% of CG.
Cleared "A Stray Sheep".
Cleared "Closed Epigraph".
Opened TIPS List.
Cleared "Missing Link".
Answered a message from someone.
Began Steins;Gate 0.
100% Completed Steins;Gate 0.
Cleared "Presage or Recognize".
Cleared "Vega and Altair".
Cleared "Gehenna's Stigma".
Cleared "Milky-way Crossing".
Saw all CG.
Saw all TIPS.
Read and ignored a message.