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