You can add a menu section to a page using the following shortcode:
Where 1 is the ID of the menu section.
To use this shortcode on the page edit screen, just click the + button and add a new shortcode block to the page. Then write or paste in the above shortcode.
The fdm-menu-section shortcode takes the following attributes:
id Accepts the taxonomy term ID of the desired menu section. Must be an integer.