In order to complete the prerequisites, you need to create a Box Content App, follow the next steps:
Create the Box Content App
Go to this URL https://app.box.com/developers/services/edit/ and login using the admin user account.
Select a custom application and click Next.
Select Standard OAuth 2.0 type of Authentication, click the option and Next.
Type an application name, click Create App button.
Click on Configure your application
Copy the client id and the client secret values for the content source configuration. Verify the scopes and check the option ‘Perform actions as Users’. This is required if you want to crawl private information from all users.
Save the application