Here is the full list of all 50 Starfield achievements. It takes around 100-120 hours to unlock all of the achievements on Windows.
Modify a Ship
Eliminate 300 Human Enemies
Join the Freestar Rangers
Bypass 50 Digital Locks
Complete "Executive Level"
Access 50 Computers
Complete "Guilty Parties"
Join Ryujin Industries
Complete "Into the Unknown"
Reach Level 10
Produce 500 Total Resources from Outposts
Build an Outpost
Join Constellation
Reach Level 5
Enter Space for the First Time
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"
Join the UC Vanguard
Complete "The Devils You Know"
Complete "A Legacy Forged"
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 20 Star Systems
Visit all Star Systems
Land on 100 Planets
Complete 30 Activities
Complete 30 Terminal or Misc. Missions
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 25
Reach Level 50
Reach Level 100