Here is the full list of all 50 Starfield achievements. It takes around 100-120 hours to unlock all of the achievements on Windows.
Complete "The Devils You Know"
Complete 30 Terminal or Misc. Missions
Complete 30 Activities
Join Ryujin Industries
Join the Freestar Rangers
Reach Level 10
Join the UC Vanguard
Reach Level 5
Join Constellation
Enter Space for the First Time
Complete "Into the Unknown"
Complete "All That Money Can Buy"
Complete "Further Into the Unknown"
Complete "High Price to Pay"
Complete "In Their Footsteps"
Complete "Entangled"
Complete "Unearthed"
Complete "One Giant Leap"
Complete "A Legacy Forged"
Complete "Surgical Strike"
Complete "The Hammer Falls"
Complete "Guilty Parties"
Complete "Executive Level"
Join the Crimson Fleet
Complete "The Best There Is"
Complete "Legacy's End"
Build an Outpost
Connect 5 Outposts with Cargo Links
Produce 500 Total Resources from Outposts
Modify a Ship
Visit 20 Star Systems
Visit all Star Systems
Land on 100 Planets
Gather 500 Organic Resources
Gather 500 Inorganic Resources
Bypass 50 Digital Locks
Access 50 Computers
Mod 50 Weapons
Craft 100 Items
Recruit 10 Separate Companions
Reach Maximum Relationship Level with a Companion
Collect 20 Quantum Essence
Collect 10 Ships
Read 20 Skill Magazines
Eliminate 300 Human Enemies
Eliminate 300 Creatures
Successfully Smuggle Contraband
Reach Level 25
Reach Level 50
Reach Level 100