Moving category link from above posts title to under post titles

Class
<div class="entry-categories">

From Parent Twenty Twenty, duplicate this directory and file template-parts/entry-header.php and paste in Child theme.
Move this code

/**
 * Allow child themes and plugins to filter the display of the categories in the entry header.
 *
 * @since Twenty Twenty 1.0
 *
 * @param bool Whether to show the categories in header. Default true.
 */
$show_categories = apply_filters( 'twentytwenty_show_categories_in_entry_header', true );

if ( true === $show_categories && has_category() ) {
	?>

	<div class="entry-categories">
		<span class="screen-reader-text"><?php _e( 'Categories', 'twentytwenty' ); ?></span>
		<div class="entry-categories-inner">
			<?php the_category( ' ' ); ?>
		</div><!-- .entry-categories-inner -->
	</div><!-- .entry-categories -->

	<?php
}

Placed between excerpt and post meta

if ( is_singular() ) {
	the_title( '<h1 class="entry-title">', '</h1>' );
} else {
	the_title( '<h2 class="entry-title heading-size-1"><a href="' . esc_url( get_permalink() ) . '">', '</a></h2>' );
}

$intro_text_width = '';

if ( is_singular() ) {
	$intro_text_width = ' small';
} else {
	$intro_text_width = ' thin';
}

if ( has_excerpt() && is_singular() ) {
	?>

	<div class="intro-text section-inner max-percentage<?php echo $intro_text_width; // phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped -- static output ?>">
		<?php the_excerpt(); ?>
	</div>

	<?php
}

/**
 * Allow child themes and plugins to filter the display of the categories in the entry header.
 *
 * @since Twenty Twenty 1.0
 *
 * @param bool Whether to show the categories in header. Default true.
 */
$show_categories = apply_filters( 'twentytwenty_show_categories_in_entry_header', true );

if ( true === $show_categories && has_category() ) {
	?>

	<div class="entry-categories">
		<span class="screen-reader-text"><?php _e( 'Categories', 'twentytwenty' ); ?></span>
		<div class="entry-categories-inner">
			<?php the_category( ' ' ); ?>
		</div><!-- .entry-categories-inner -->
	</div><!-- .entry-categories -->

	<?php
}

// Default to displaying the post meta.
twentytwenty_the_post_meta( get_the_ID(), 'single-top' );
?>