Need Help in coding

Total number of questions in a quiz.

$quiz_id = 5; // change to the quiz ID
			
$args = array(
    'post_type'      => 'post_type_questionna',
    'posts_per_page' => -1, // get all posts
    'tax_query' => array(
        'relation' => 'AND',
        array(
            'taxonomy' => 'quiz',
            'field'    => 'term_id',
            'terms'    => $quiz_id
        )
    )
);
$q = new WP_Query( $args );
echo $q->post_count; // prints total questions in that quiz

how can I Show the total Quiz Questions posted by authors. I have tried this but didn’t get any result.

Not tested, but something like this should work.

$author_id = 0; // change to the ID of the author you want to count
			
$args = array(
    'post_type'      => 'post_type_questionna',
    'posts_per_page' => -1,
    'author' => $author_id
);
$q = new WP_Query( $args );
echo $q->post_count; // prints total questions created by author

For that, you can just remove the tax_query array since it’s not needed. Just keep the post_type and posts_per_page parameters. This will show the total # of questions across ALL quizzes.