If you don’t like the vertical menu in MentalPress, you can easily change it to horizontal menu.
Go to Appearance > Menus > Select menu to edit > choose Main menu
Scroll down to Menu Settings > Theme Locations > uncheck Main Menu
Save.
Now go to Appearance > Widgets > Header > remove widgets that are currently in your header section and drag&drop Custom menu Widget > Select Menu > Main Menu
Now you should have horizontal menu. Please note, that this will impact your mobile menu, which won’t be toggled. This is how it will look on mobile: