Using the “One-click demo import” plugin, You can import the Rentle theme demo content with a single click.
Go to Appearance-> Import Demo Data. And click on the Import Demo Data button.
The demo import option lets you import the following:
1. It imports all posts, pages, custom post type content, images
2. Imports menus, custom fields, categories, tags, and comments
3. Imports all the data of the plugins used, widgets, Customizer settings & the front page.