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