My question is close to other questions, but I dont\' have enough reputation to comment.

I\'m working for a restaurant and I \'d like, for my menu page, to organise my posts "meal" under terms "cat_meal".

This terms should respect an order (dessert after starter for example). And that\'s my probleme : I tried so many snippets, that I don\'t know which one I should write here... Here are some picture to explain, I hope. But, there is always something wrong : either I can display my term in a right order and my query post is not good. Or meal posts are under the good terms, but, the order of the terms are wrong. Or, worth, nothing happens.

Here are two tests, thanks for your time and help :

$args_tax = [
    \'parent\'    => 0,
    \'hide_empty\' => 0,
    \'meta_key\'      => \'ordre\',// I added an ACF with number from 1 to 8 to order
    \'orderby\'   => \'meta_value\',
    \'order\'     => \'ASC\'
];

$terms = get_terms(\'cat_meal\', $args_tax); // tax cat_meal
// print_r($terms);

if (!empty($terms)):
    foreach ($terms as $term):
        $argsPost = [
            \'post_type\' => \'meal\',//CPT meal
             \'posts_per_page\' => -1
        ];

        $query = new WP_Query($argsPost);
        while ($query->have_posts()) : $query->the_post();
            echo $term->name ;
            the_title();
        endwhile;
        wp_reset_postdata(); // reset the query 
    endforeach;
endif;
//PROBLEM : under each term, every posts are displaying ! I don\'t understand why...

Second version from this question Get all categories and posts in those categories

$args = array( 
        \'post_type\' => \'meal\',  
        \'posts_per_page\' => -1
    );

    $query = new WP_Query($args);   
    $q = array();

    while ( $query->have_posts() ) { 
        $query->the_post(); 
        $a = \'\' . get_the_title() .\'\';
        $terms = wp_get_post_terms( $post->ID, \'cat_meal\', $args );
        foreach ( $terms as $term) {
            $term_link = get_term_link( $term );
            $b = \'\'.$term->name.\'\';    
        }
        $q[$b][] = $a; 
    }
    wp_reset_postdata();
    foreach ($q as $key=>$values) {
        echo $key;
            foreach ($values as $value){
                echo $value;
            }
    }

The posts are well displaying under the terms, BUT the terms have wrong order (dessert before pizza)

I\'ve just found this answer too, but I\' dont undetsand wher the taxonomy is declared : Ordering Posts with Custom Taxonomy Terms Array.

I would really appreciate some advices into my fog : thanks