First of all, to edit the page with Elementor by simple clicking on Edit with Elementor button. It will redirect you to the Elementor's Editing Mode where you will have Elementor's Widget Panel on left and Page's Preview on the right.
The page must have Full Width or Fluid Width Page Template assigned.
The very first step is to set a full width container with no gaps. Please check out the following video.
To add any Real Homes Widget simply drag the widget to the right as shown in the following videos (double click to video for full screen mode).