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