1) first install scripthookV2 and LML mods on rdr2 before

go here 

https://www.nexusmods.com/reddeadredemption2/mods/1472?tab=files

download "MOD LOADER" and "ScriptHookRDR2 V2"

2) after go to 

https://www.rdr2mods.com/downloads/rdr2/tools/76-lennys-mod-loader-rdr/

download and install

Now mods will working on your game.

3) after go to https://www.nexusmods.com/reddeadredemption2/mods/5285

download and install on your game 

4) verify if the vehicule trainer is working first and

5) when working, you can start install my mod.

VERY IMPORTANT : all my mods ever diffuse will be on the trainer list at each new mods.

unfortenatly, for not paid members, some vehicules in the list will not be avaible..

enjoy

Bastoudu66.