There are many solutions now to build Minimum viable product using Drupal 8, using rest api, Json
Drupal 8 actually provides a lot of capabilities for decouple frontend using headless Drupal.
But what was with Drupal 7? not straight forward solution with Drupal 7.
With Drupal 7, using paragraph and field collection Content modeled as Entities.
With custom Drupal modules and entities to generate Json for each Entity and moving these files to frontend.
With Scheduler module to un/publish contents and with Jenkins to move files between directories.