How to display categories instead of tags in WordPress?

Question

metadata

Good afternoon!
Redesigning a WordPress theme. Entries to be displayed in the slider are displayed based on tags. I don't know who came up with this, but it's true.
Found the code that does this. How can I change it to have categories instead of tags?

// Pull all tags into an array.
$tags = array();
$tags_obj = get_tags();
foreach ( $tags_obj as $tag ) {
  $tags[$tag->term_id] = esc_html( $tag->name );
}