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