So I made a list where I found all games that compatible with 32-bit Windows, so let's get started!
Mafia: The City of Lost Heaven & Mafia 2
All Grand Theft Auto Games Compatible with 32-bit PCs except Grand Theft Auto V (Vice City Stories, Liberty City Stories & Chinatown Wars are Console Exclusives, you can run them with emulators, it only depends on the emulator that support 32-bit or 64-bit)
Max Payne, Max Payne 2: The Fall of Max Payne & Max Payne 3
Dead Rising 2 & Over The Record standalone expansion (3 & 4 not compatible as well as the first DR because it's a remaster)
Deadpool The Game
Rules of Survival (Official PC Version)
Killing Floor (Second Killing Floor isn't compatible)
GUN (2005 wild west shooter like Red Dead Revolver and Redemption)
Borderlands, Borderlands 2, Borderlands The Pre-Sequel! & Tales of Borderlands
All Hitman Games except HITMAN 2016 and HITMAN Season Two when it comes out
All Test Drive Games Compatible with 32-bit PCs
Halo: Combat Evolved
All Dead or Alive Games until Last Round & LR Core Fighters
Planetside 2
ORION: Prelude ($9.99 on Steam)
All Splinter Cells until Conviction, not sure about Blacklist
Minecraft & Minecraft: Story Mode
The Walking Dead Season One (not sure about the rest)
All Resident Evil Games Compatible with 32-bit PCs except RESIDENT EVIL 7: BIOHAZARD & the upcoming RE2 Remake
Crossout
Just Cause & JC2 (3 not compatible as well as 4 when it comes out)
Rocket League
Sleeping Dogs (Only all versions until 2.1 which is the Limited Edition while the Definitive Edition isn't compatible as it's a complete overhaul/remaster of the game)
Portal & Portal 2
All The Elder Scrolls Games Compatible with 32-bit PCs except Skyrim Special Edition
All Call of Duty Games Compatible with 32-bit PCs except Advanced Warfare, Black Ops 3, Modern Warfare Remastered & Infinite Warfare as well as Black Ops 4 (Ghosts may work with RAM Fix but I don't know)
All Prince of Persia Games Compatible with 32-bit PCs
All Commandos (Made by Eidos or Square Enix now) Games Compatible with 32-bit PCs
All DiRT Games Compatible with 32-bit PCs except DiRT Rally & DiRT 4
Bully Scholarship Edition
Blood and Bacon (On Steam for $0.99)
America's Army: Proving Grounds (Free to Play on Steam)
Injustice: Gods Among Us Ultimate Edition (Exclusive PC version bundled with all DLC) (Injustice 2 isn't compatible)
All Fallout Games Compatible with 32-bit PCs except Fallout 4 and Fallout '76
Project CARS (It's normally 64-bit, but you can make it 32-bit compatible by adding a launch parameter "-x86" without the quotes or launch the 32-bit executable) & Project CARS Pagani Edition (Free to Play on Steam)
All Assassin's Creed Games Compatible with 32-bit PCs except AC Rogue, AC Unity & AC Syndicate & Origins alongside with Discovery Tour
Garry's Mod
Unturned
All of Valve's Games (All Counter-Strikes, Team Fortress Classic & 2, all) (Not sure about HUNT DOWN THE FREEMAN)
All Need For Speed Games Compatible with 32-bit PCs except NFS 2015 & Payback (Some people say NFS Rivals 32-bit compatible but I'm not sure, give it a try if you want it)
PAYDAY: The Heist & PAYDAY 2: Ultimate Edition (Note that 1% of the time Golden Grin Casino would work on 32-bit PCs, specially if you have 64-bit but 4GB RAM because the heist is intensive and would crash on 32-bit)
X-COM: UFO Defense
The Bureau: X-COM Classified
Starpoint Gemini 2
Dungeons 2
Chivalry: Medieval Warfare
Outland
Heaven Island VR MMO & Heaven Island Life (Probably the only VR games that support 32-bit lol)
Tactical Intervention (Free to Play on Steam)
Woodle Tree Adventures
State of Decay (Not sure if the YEAR ONE Survival Edition is, because YOSE COMPLETELY Improves the graphics and adds new DLCs more like a remaster)
Burnout Paradise The Ultimate Box
SUPERHOT (VR version isn't compatible)
Sniper Elite, Sniper Elite V2 & Sniper Elite 3 (The 4th one isn't compatible)
All Tomb Raider Games Compatible with 32-bit PCs except Rise of The Tomb Raider & Shadow of The Tomb Raider (When it comes out)
All Devil May Cry Games Compatible with 32-bit PCs (HD Collection will not work)
All Batman Games (before Arkham Series evolve and after it did) Compatible with 32-bit PCs except Arkham Knight
All ArmA Games Compatible with 32-bit PCs except ArmA 3 (If you got the very old 2013 alpha version may work)
All The Witcher Games Compatible with 32-bit PCs except Witcher 3 Wild Hunt
All Battlefield Games Compatible with 32-bit PCs except Hardline & BF1 & BF5 (Maybe BF3? they say BF3 is 64-bit only but how BF4 is 32-bit compatible? How does that make any sense lol)
Gears of War (The First one was released on PC)
Vampire The Masquerade
BloodRayne 1 & 2
All Medal of Honor Games until the 2010 reboot (not sure about Warfighter)
Rogue Troops
Blades of Time
Spore
Constantine The Game
All Bioshock Games Compatible with 32-bit PCs except the Remastered versions
All DOOM Games Compatible with 32-bit PCs except DOOM 2016
Metro 2033 & Metro Last Light (Remastered (Redux) versions not compatible with 32-bit PCs)
Dishonored (Dishonored 2 not compatible with 32-bit PCs)
All Far Cry Games Compatible including Blood Dragon standalone expansion with 32-bit PCs except FC4 & FC Primal & FC5
All Mortal Kombat Games Compatible with 32-bit PCs except Mortal Kombat X or XL (XL is X but with all DLC)
Mirror's Edge (Catalyst not compatible with 32-bit PCs)
All Mass Effect Games Compatible with 32-bit PCs except Andromeda
PREY (The 2006 release) PREY 2017 not compatible with 32-bit PCs
All Street Fighter Games Compatible with 32-bit PCs except Street Fighter V & SFV Arcade Edition
Sniper: Ghost Warrior 1 & 2 (The 3rd one not compatible with 32-bit PCs)
The Sims, Sims 2 & Sims 3 are compatible with all expansion packs including Sims 4
THIEF: The Dark Project, THIEF: Gold, THIEF 2: The Metal Age, THIEF 3: Deadly Shadows are compatible with 32-bit PCs including THIEF 2014 (tested by myself) (But whats the difference between TDP and Gold? TDP is discontinued and Gold is actually TDP with more chapters and fixes, BUT TO MAKE THEM ALL RUN ON MODERN PCS YOU NEED TO DOWNLOAD TFIX FOR GOLD, DFIX FOR TMA AND SNEAKY UPGRADE GOLD EDITION FOR DS)
All Red Faction Games Compatible with 32-bit PCs except Red Faction Guerrilla Re-mars-tered version
Zombie Army Trilogy (It works also it's a remaster of Sniper Elite Nazi Army 1 & 2 adding a new chapter with Left 4 Dead 1&2 characters)
The Punisher (by Volition)
Haydee ($14.99 on Steam)
Renegade Ops
Paladins: Champions of The Realm
Ridge Racer Unbounded
All Spider-Man (Before The Amazing series) Games Compatible with 32-bit PCs except the 2nd Amazing game
All Saints Row Games except Agents of Mayhem
Tencent Gaming Buddy (Official PUBG Mobile Emulator)
And ANY Console Game can work on 32-bit PCs if the emulator supports them (PS1, PS2, PSP, Wii, GBA, NES, SNES, Dreamcast, Gamecube, GBC, etc. But not PS3/X360/Wii U/PS4/X1/Switch) Even Android, can run PUBG Mobile on your 32-bit PC without having the original 30GB PUBG on Steam!
VR Games not compatible with 32-bit except few but still not played by tons of people
Support this list by sharing it, cause I spent a long time finding the games that can work on 32-bit PCs for you guys to get and enjoy! :)