This will typically be in folder in “ :\Users\\Documents\Electronic Arts\The Sims 4\Mods.” (Replace your own Windows user name and the letter for your hard drive.
Some mods may have specific installation instructions, but most CC should be able to be installed with the following steps.
We’ve detailed the steps on installing mods and CC below. (You cannot install or use mods and CC on consoles.) Our The Sims 4 guide will walk you through how to install CC and mods for both Windows and Mac. Installing them can be complicated if you’re new to modding games, but The Sims 4 makes it fairly easy. If you’re playing The Sims 4 on Windows or Mac, you can customize the game using custom content (CC) and mods.