functions.php

<?php

function be_get_block( $blockName = '' ) {
  global $post;
  $blocks = parse_blocks( $post->post_content );
  foreach( $blocks as $block ) {
    if( $blockName === $block['blockName'] )
      return render_block( $block );
}
  
// Example Usage 
echo be_get_block( 'core/quote' );