The only configuration value that you need to supply to Create React App so that it can bootstrap your project is the name. This is specified as an argument to the create-react-app command:
$ create-react-app my-react-app
This will create a my-react-app directory in your current directory, if it doesn't already exist. If it already exists, the directory will be used. This is where you'll find everything to do with your application. Once the directory is created, it installs package dependencies and creates project directories and files. Here's a shortened version of what the create-react-app command output might look like:
Creating a new React app in 02/my-react-app. Installing packages. This might take a couple ...