Hello.
The navbar block still does not have a “vertical” setting, but here is a workaround until its supported:
29/08/2019: We have updated the settings to allow vertical orientation.
To create a homepage:
1 – Start with a 2 column container, set the width to 20% – 80% for each in desktop view. Make it responsive setting the columns width to 100% in tablet view.
2 – Place a menu navbar in the left column.
3 – After installing your theme, set “Vertical orientation” to “Yes” under your current menu WordPress customizer settings.

To create internal pages:
1. Repeat the previous layout inside an “extra page template” block.
2. You will use a fresh navbar block to create another menu that you will set up later in WordPress.
3 – After installing your theme, set “Vertical orientation” to “Yes” under your current menu WordPress customizer settings.
4 – Assign the “Page template 1” in WordPress.
Video tutorial: https://www.youtube.com/watch?v=gvxocH-0nxw


Sample project:
You can download and import a sample project – DOWNLOAD IT HERE – (unzip and import in Themes Generator).
Homepage and internal pages screenshots:

