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