The accordion can be published in posts and pages, in widgets, and also in PHP code.
In posts and pages you need to use the shortcode provided in the Grid Accordion -> All Accordionspage, like this:
In PHP code, you need to use the
do_shortcode() call and provide the actual shortcode as an argument, like this:
<?php echo do_shortcode( '[grid_accordion id="3"]' ); ?>
Note: When you add the accordion in PHP code, the plugin won't be able to detect the presence of the accordion there so it won't be able to automatically load the necessary CSS files. Because of this, you need to go to the Grid Accordion -> Plugin Settings page and set the Load stylesheetssetting to On homepage if you load the accordion on the homepage or to On all pages if you load the accordion in other pages.