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