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