PHP

wordpress get post taxonomy terms

//Get selected terms of a post by taxonomy
$selectedTerms = wp_get_post_terms(get_the_ID(),'TAXONOMY_NAME');
foreach($selectedTerms as $term){
	echo $term->name;
}

wordpress get terms by taxonomy

You need to pass an additional argument to get_terms(). The default is to hide
"empty" terms-- terms which are assigned to no posts.

$terms = get_terms([
    'taxonomy' => $taxonomy,
    'hide_empty' => false,
]);

wordpress get current taxonomy

$term = get_term_by( 'slug', get_query_var( 'term' ), get_query_var( 'taxonomy' ) );
echo $term->name; // will show the name
echo $term->slug; // will show the slug

How do I get current taxonomy "term id" on wordpress?

$obj = get_queried_object();
echo $obj->term_id;