Hi there, Boardwalk only comes with a toggle menu, not a traditional menu.
To add a traditional menu, you could create a child theme* and add a different style of menu to it, using this function:
https://codex.ww.wp.xz.cn/Function_Reference/wp_nav_menu
The file you’d want to look at is header.php, in addition to adding new styles to the child’s stylesheet.
Making this kind of change isn’t extremely simple, but it’s certainly doable if you’re comfortable with HTML, CSS, and a bit of WordPress theme structure.
Let me know how it goes!
* Using a child theme means that your tweaks won’t be overwritten when updating the theme. Here are some guides in case you haven’t made one before:
http://codex.ww.wp.xz.cn/Child_Themes
http://op111.net/53/