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 Derelict Citadel Survey
Finish Crimson Wastes Survey
Finish Fractured Wastes Survey
Finish Overgrown Ruins Survey
Gain a moment of peace
Open the Locked Door
Kill 100 Hostiles with Disgorgers
Defeat Algos' final form
Defeat Algos' first form
Finish Echoing Ruins Survey
Finish Act 3
Complete all House sequences
Achieve Weapon Proficiency level 30
Finish Act 2
Defeat Ophion
Defeat Hyperion
Finish Calculated Risk
Finish Act 1
Defeat Nemesis
Have 5 Parasites simultaneously
Complete a Xeno-archive set (excluding Tower of Sisyphus)
Complete the first Hospital sequence
Die and return in the Tower
Achieve 200% Max Integrity
Defeat Ixion
Perform 5 successful Overloads in a row
Complete a daily challenge in Simulation Mode
Unlock all translation tiers of a Xenoglyph
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
Experience a new cycle after death