Full list of all 23 Destiny 2 achievements. It takes around 200 hours to unlock all of the achievements in the base game on Windows.
The base game contains 13 achievements, and there is 1 DLC pack containing 10 achievements.
Acquire each Warlock subclass.
Acquire each Titan subclass.
Complete the Leviathan raid.
Complete the Leviathan raid on Prestige difficulty.
Encounter an Agent of the Nine somewhere in the system.
Acquire each Hunter subclass.
Complete Introduction: Crucible.
Complete a Flashpoint on Earth, Titan, Nessus, or Io.
Complete a Heroic public event.
Complete a Nightfall strike.
Collect 15 Red War exotic weapons or armor.
Complete 30 challenges.
Reach level 20.
Complete a Triumph Seal.
Complete the "Last Wish" Raid.
Pursue Uldren and the Fanatic to the Watchtower, and finish what you started.
Collect 10 Forsaken Exotic weapons or armor.
Complete a Collections Badge.
Defeat a Forsaken Nightfall Boss.
Complete a Forsaken Exotic Quest.
Win a Gambit match.
Enter the Dreaming City.
Earn 5,000 Triumph points.