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