Dawn Theme: problem with the dropdown menu items

[Laimomo]

Hello and thanks in advance to those who can help me.

I'm working on the Dawn Theme.
I've moved the Main Menù in the left sidebar position.

Now I'm facing a problem and I try to explain it with image and link.

The actual website:

this is how I would like to have the menu:

Actual website link: https://handsoffashion.com/pages/home-page-3

an example of a website with the menu I would like to have: 
https://www.colvilleofficial.com/