Here is the full list of all 50 Starfield achievements. It takes around 100-120 hours to unlock all of the achievements on Windows.
Read 20 Skill Magazines
Reach Maximum Relationship Level with a Companion
Craft 100 Items
Reach Level 25
Visit 20 Star Systems
Eliminate 300 Human Enemies
Complete "All That Money Can Buy"
Complete 30 Terminal or Misc. Missions
Access 50 Computers
Complete 30 Activities
Join Ryujin Industries
Modify a Ship
Complete "Into the Unknown"
Reach Level 10
Build an Outpost
Reach Level 5
Join Constellation
Enter Space for the First Time
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"
Join the Freestar Rangers
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"
Connect 5 Outposts with Cargo Links
Produce 500 Total Resources from Outposts
Visit all Star Systems
Land on 100 Planets
Gather 500 Organic Resources
Gather 500 Inorganic Resources
Bypass 50 Digital Locks
Mod 50 Weapons
Recruit 10 Separate Companions
Collect 20 Quantum Essence
Collect 10 Ships
Eliminate 300 Creatures
Successfully Smuggle Contraband
Reach Level 50
Reach Level 100