First, I'd like to clarify that the Feature Box is an SP Page Builder addon, not a Joomla module. These are two different elements within the Joomla ecosystem.
Regarding the issue of the addon not displaying: this was due to the media position not being selected. I’ve gone ahead and selected the appropriate media position, and the addon is now displaying correctly tinyurl.com/yq6xr44d . Please take a moment to review it on your end.
As for the submenu not appearing, this was related to Joomla’s cache. I’ve cleared the cache, and the submenu is now visible as expected.
Kindly check both updates and let me know if everything looks good or if you need further assistance.
Best regards