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 "High Price to Pay"
Complete "Further Into the Unknown"
Complete "All That Money Can Buy"
Complete "Into the Unknown"
Reach Level 25
Eliminate 300 Human Enemies
Visit 20 Star Systems
Access 50 Computers
Complete 30 Activities
Complete "A Legacy Forged"
Complete "Executive Level"
Complete "Guilty Parties"
Bypass 50 Digital Locks
Complete 30 Terminal or Misc. Missions
Produce 500 Total Resources from Outposts
Build an Outpost
Complete "The Devils You Know"
Join the UC Vanguard
Reach Level 10
Modify a Ship
Join Ryujin Industries
Reach Level 5
Join Constellation
Enter Space for the First Time
Complete "In Their Footsteps"
Complete "Entangled"
Complete "Unearthed"
Complete "One Giant Leap"
Join the Freestar Rangers
Complete "Surgical Strike"
Complete "The Hammer Falls"
Join the Crimson Fleet
Complete "The Best There Is"
Complete "Legacy's End"
Connect 5 Outposts with Cargo Links
Visit all Star Systems
Land on 100 Planets
Gather 500 Organic Resources
Gather 500 Inorganic Resources
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 Creatures
Successfully Smuggle Contraband
Reach Level 50
Reach Level 100