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