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.
Reach level 20.
Complete Introduction: Crucible.
Complete a Heroic public event.
Collect 15 Red War exotic weapons or armor.
Acquire each Titan subclass.
Acquire each Warlock subclass.
Complete a Flashpoint on Earth, Titan, Nessus, or Io.
Complete 30 challenges.
Acquire each Hunter subclass.
Complete a Nightfall strike.
Complete the Leviathan raid.
Complete the Leviathan raid on Prestige difficulty.
Encounter an Agent of the Nine somewhere in the system.
Earn 5,000 Triumph points.
Collect 10 Forsaken Exotic weapons or armor.
Complete a Triumph Seal.
Complete a Collections Badge.
Enter the Dreaming City.
Complete a Forsaken Exotic Quest.
Win a Gambit match.
Defeat a Forsaken Nightfall Boss.
Pursue Uldren and the Fanatic to the Watchtower, and finish what you started.
Complete the "Last Wish" Raid.