Create Next.js site
Create a Next.js site on Drupal
Start by creating a Next.js site so that we can render the preview on Drupal.
- Visit 
/admin/config/services/next. - Click Add Next.js site.
 - Fill in the following values:
 
- Label: 
Next.js - Base URL: 
http://localhost:3000 - Preview URL: 
http://localhost:3000/api/preview - Preview secret: 
secret 
As from next-drupal 1.5, encrypted secrets are automatically generated and validated by the Next module.
- Click Save