Plutonium

The game is very poorly optimized on PC, but if you have 800 on BO2 then yeah you shouldn't get around 30 on BO1
Try these solutions
https://plutonium.pw/docs/low-fps/

These are actual mods that you have to put them in the mods folder and activated them in the game menu before launching the match heres 2 of them that i really love😆
https://forum.plutonium.pw/topic/38256/release-zm-mod-zm_perks-adding-all-perks-to-maps

https://forum.plutonium.pw/topic/37621/release-zm-mod-zm_weapons-adding-all-weapons-to-maps/179

Racoon_ youtube videos are way old and outdated... use the texture guide on the official plutonium.pw website.

the t6r folder has been a no no for a while now (years) and the latest update finally killed it.

custom textures go into storage/t6/images folder in your plutonium directory.

Racoon_ it's called a folder not a file, a folder holds file(s)
As for loading textures the method has never changed, the doc is still here and the instructions are still the same
https://plutonium.pw/docs/modding/loading-textures/