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