I am trying to mod nee Master of Magic everything I have found says to add to the mods folder but I don't have a mods folder I have made one and add the mod I want but I still can't use it

I had the same issue until I realized I was in the wrong directory. You want to go to "Users/NAME/AppData/LocalLow/Muha Games/MoM/Mods" not the game directory. Just adding this in since I couldn't easily find this answer online either.