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