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