1. Download and install Ped Damage Overhaul, only install the .asi file that comes with it.
https://www.nexusmods.com/reddeadredemption2/mods/184

2. Place the PedDamageOverhaul.ini inside the RDR2 Root Folder in the RDR2 main folder. 
You may edit the settings I changed to your liking.
They will  be marked with ;MySettings

3. Done!

This is a list of mods I reccomend pairing with my PDO settings:

Anatomical Damage 1899 Firearms Edition
https://www.nexusmods.com/reddeadredemption2/mods/1431

Aaron's Ped Accuracy Fix
https://www.nexusmods.com/reddeadredemption2/mods/2268

Realistic Navigation
https://www.nexusmods.com/reddeadredemption2/mods/983

Combat Experience
https://www.nexusmods.com/reddeadredemption2/mods/1025

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⠀⠀⠀⢠⣍⠹⣿⣿⡇⠀⠀⠀⠀⠀⠀⠀⠀⢹⣿⣿⣿⣿⣿⣿⡿⠀⠀⠀⠀⠀
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⠀⠀⠀⠀⠀⠀⠻⠿⠟⠁⠑⢶⣤⣴⣿⣿⣿⣷⣶⣬⣿⣿⣿⡿⠀⠀⠀⠀⠀⠀
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⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠻⢿⡿⠟andré⠀⠀⠀⠀⠀