Installation:
For NoFallDamage without Unlimited Weight
1. Download the NoFallDamageOnly-V1.0 file
2. Open file explorer and navigate to [Drive that your game is installed in]:\SteamLibrary\steamapps\common\KingdomComeDeliverance
3. Go to your Mods folder, if you do not have one, make a new folder and name it 'Mods'
4. Open the zip file you downloaded, and drag and drop the NoFallDamageOnly folder into the Mods folder.
5. Done

For NoFallDamage WITH Unlimited Weight
This mod has conflicts with the Unlimited Weight mod, or any mod that changes the rpg_param.xml table.
Since it's possible there is no conflicts with other mods the steps should be the same as above.
I myself tried using the NoFallDamage mod and the Unlimited Weight mod seperately and it is worked for me.
I can't be certain since it could be a fluke, but I believe this mod can be used together with the Unlimited Weight mod or any mod that edits the rpg_param.xml table as this mod was done using the "best practice" to only edit mod-specific table files with individual rows as stated in the KCD Modding Guide:

With game versions 1.9.5 and later:
If you're making a mod that overrides a parameter file inside "Tables.pak" — it is now BEST PRACTICE to create mod-specific table files with individual rows — instead of overwriting the whole table.

in which case, you can download the NoFallDamageOnly file and it should work with the Unlimited Weight mod.
In case it does not work, (or you want to have a cleaner Mods folder AND prevent any possible conflicts with other mods, you can still follow these steps:

1. Download the NoFallDamageandUnlimitedWeight-V1.0 file
2. Open file explorer and navigate to [Drive that your game is installed in]:\SteamLibrary\steamapps\common\KingdomComeDeliverance\Mods
3. Delete your UnlimitedWeight mod folder
4. Open the NoFallDamageandUnlimitedWeight-V1.0 file
5. Drag and drop the NoFallDamageandUnlimitedWeight folder into your Mods folder
6. Done