You can find a lot of video tutorial that will help you to understand how to edit our theme page with WPBakery Page Builder https://wpbakery.com/video-tutorials/
Thank you for your feedback.
I understand how to edit with WPBakery page builder, but in this theme, I do not know where are these sections that I show you on the screenshoot.
Could you tell me where these sections are inside the theme, please?