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