How to display author name and category on my posts?

In loop
<?php the_author(); ?>

<?php $post_detail = get_the_terms( $post->ID, ‘taxonomyname’);
$cat_id = $post_detail[0]->term_id;
$cat_name = $post_detail[0]->name;
echo $cat_name; ?>

Thanks but I’m not sure where to paste all this. What is ‘In loop’?

To get author name in loop.
<?php the_author(); ?>

To get author name without loop.
$author_id=$post->post_author;
<?php echo the_author_meta( ‘display_name’ , $author_id ); ?>

To get category name.
<?php $post_detail = get_the_terms( $post->ID, ‘taxonomyname’);
$cat_id = $post_detail[0]->term_id;
$cat_name = $post_detail[0]->name;
echo $cat_name; ?>

Hi Yvonne,

Apex only adds the date for the posts on the blog, but the categories and tags are displayed on the post page at the bottom: https://pics.competethemes.com/image/1p16291a3b3T

To display the author name, what about using a plugin like this to add a bio section after each post: https://www.ads-software.com/plugins/starbox/

Would that work well for your site?