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