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