The mods folder is installed by default, along with it's Resource.cfg. As shown in the photos below.
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If you don't have this type of setup. You may want to try a Sims 4 factory reset, so the folder can be set up correctly.
Sims 4 Factory Reset - (What & Howto)
http://www.carls-sims-4-guide.com/forum/index.php?topic=29292.msg401669#msg401669If you want the Cheats Fix mod, download it and then copy it from where you downloaded it to your Sims 4 mods folder.
C:\Users\Username\Documents\Electronic Arts\The Sims 4\Mods
Make sure both mods/cc options are check marked in the Game Options.
-- Options > Game options > Other - Enable Custom Content and Mods, and Script Mods Allowed
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You will need to exit the game and reload it for the mod to show as active when loading the game.
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This mod does fix Skill Cheats -
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