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