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