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