Hi there! sorry for the slow response,
you can follow the install instruction on the itch page or in our documentation.
here's the quick guide on how to do that:
Unity Installation (minimum version: Unity 2019.4)
Import the .unitypackage files into your project
Click the menu: "Window/Character Creator 2D/Create Character" to refresh the parts
Standalone Installation
Install or put the .pack files into "Your Character Creator 2D Installation Folder/Packs" folder
Run your Character Creator 2D standalone