Here is the full list of all 49 Metro 2033 Redux achievements. It takes around 25-30 hours to unlock all of the achievements on Windows.
Become a true ranger.
Complete the game in Spartan Mode.
Kill 10 Spiders.
Kill 5 amoebas.
Complete FRONTLINE level without killing anyone.
Spend 60 seconds in a Radiation Hotspot.
Kill 30 enemies with flame grenades.
Complete the level BLACK STATION without killing or knocking out any enemies.
Knock 30 human enemies out in close combat.
Kill 30 human enemies in close combat.
Explode 30 enemies.
Make 30 deals in weapon shops.
Exchange 500 Military-Grade 5.45 rounds at Exchange kiosks.
On the level FRONTLINE kill all of the enemy Red Army and Fascist Soldiers.
Kill 30 enemies with throwing knives.
Kill 100 enemies using revolvers.
On the level HUNTER kill the nosalises before they break through the ventilation grilles.
Complete all 51 of Artyom's hidden Diary pages.
Find the truth.
Complete the game in Survival Mode.
Get 30 kills with Hellbreath.
Kill at least one enemy with each weapon available in the game
Kill 30 enemies with a flamethrower.
Wipe your Gas Mask 20 times.
Kill a librarian.
Kill 200 Mutants.
Kill 50 Watchmen.
Drink at every occasion.
Kill 100 enemies with assault rifles.
Kill 15 human enemies with Headshots from at least 30 meters' distance.
On the level OUTPOST reach the radio tower and broadcast the commander's message.
Kill 2 demons.
Kill 50 humans with pneumatic weapons.
Use a Medkit 75 times.
Kill 20 lurkers.
Kill 100 enemies with shotguns.
Open 15 locked safe boxes.
Kill 100 nosalises.
On the level DEPOT silently kill the first guard and break into the Fascist station unnoticed.
Save 1000 military-grade rounds.
Disarm 15 wire traps.
Kill 100 Human Enemies.
Kill 30 human enemies with headshots.
Save a group of Reds from Fascist captivity.
Stealthily kill 15 Enemies.
Blow up the tunnel and airlock at CURSED STATION.
Find all Ranger stashes in Dead City.
Kill 10 Enemies in a row without taking any damage.
Help the poor, a coin for the kid, medicine for the sick. You help everyone you see.