get meta data from post id code example
Example 1: wp get meta field value
<?php $key_1_value = get_post_meta( get_the_ID(), 'key_1', true ); ?>
Example 2: wp get meta field value
<?php if ( get_post_meta( get_the_ID(), 'thumb', true ) ) : ?>
<a href="<?php the_permalink() ?>" rel="bookmark">
<img class="thumb" src="<?php echo esc_url( get_post_meta( get_the_ID(), 'thumb', true ) ); ?>" alt="<?php the_title_attribute(); ?>" />
</a>
<?php endif; ?>