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