I am developing a theme and I would like to know how people develop content into different sections on the index page or other pages without using “advanced custom fields” plugin so, it can be uploaded to the WordPress Directory or Themeforest without using this plugins.
I see this happening in other themes on WordPress Directory and Themeforest like the one bellow and I do not understand how this can be achieve without advanced custom fields plugin? is this done by widget? by the customizer? or how?
Example of one theme doing this:
Is there a tutorial or video tutorial someone can recommend me?