Here is the full list of all 38 Returnal achievements. It takes around 40-50 hours to unlock all of the achievements on Windows.
Finish Abyssal Scar Survey
Collect all main Achievements
Finish Crimson Wastes Survey
Finish Derelict Citadel Survey
Finish Overgrown Ruins Survey
Kill 100 Hostiles with Disgorgers
Gain a moment of peace
Open the Locked Door
Defeat Algos' final form
Finish Act 3
Finish Fractured Wastes Survey
Finish Echoing Ruins Survey
Complete all House sequences
Complete a daily challenge in Simulation Mode
Achieve Weapon Proficiency level 30
Defeat Algos' first form
Finish Act 2
Defeat Ophion
Defeat Hyperion
Complete the first Hospital sequence
Die and return in the Tower
Finish Calculated Risk
Finish Act 1
Defeat Nemesis
Achieve 200% Max Integrity
Complete a Xeno-archive set (excluding Tower of Sisyphus)
Have 5 Parasites simultaneously
Defeat Ixion
Returned by an Artifact
Retrieve 10 Scout Logs
Defeat Phrike
Unlock all translation tiers of a Xenoglyph
Complete the first House sequence
Learn the basics of survival on Atropos
Scan a Xenoglyph
Achieve maximum Adrenaline Level
Perform 5 successful Overloads in a row
Experience a new cycle after death