How to make custom pagination on classes from Bootstrap 4 in Wordpress?

Question

Bootstrap

I found a script, but it's kind of tricky. Doesn't want to change styles

<?php
if( $posts->max_num_pages <= 1 )
  return;

 $paged = get_query_var( 'paged' ) ? absint( get_query_var( 'paged' ) ) : 1;
 $max   = intval( $posts->max_num_pages );

 /** Add current page to the array */
 if ( $paged >= 1 )
  $links[] = $paged;

 /** Add the pages around the current page to the array */
 if ( $paged >= 3 ) {
  $links[] = $paged - 1;
  $links[] = $paged - 2;
 }

 if ( ( $paged + 2 ) <= $max ) {
  $links[] = $paged + 2;
  $links[] = $paged + 1;
 }

 echo '<ul class="navigation justify-content-center">' . "\n";

 /** Previous Post Link */
 if ( get_previous_posts_link() )
  printf( '<li class="page-item">%s</li>' . "\n", get_previous_posts_link() );

 /** Link to first page, plus ellipses if necessary */
 if ( ! in_array( 1, $links ) ) {
  $class = 1 == $paged ? ' class="page-item"' : '';

  printf( '<li%s><a class="page-link" href="%s">%s</a></li>' . "\n", $class, esc_url( get_pagenum_link( 1 ) ), '1' );

  if ( ! in_array( 2, $links ) )
   echo '<li class="page-item">…</li>';
 }

 // Link to current page, plus 2 pages in either direction if necessary 
 sort( $links );
 foreach ( (array) $links as $link ) {
  $class = $paged == $link ? ' class="page-item active"' : '';
  printf( '<li%s class="page-item"><a class="page-link" href="%s">%s</a></li>' . "\n", $class, esc_url( get_pagenum_link( $link ) ), $link );
    }
    

 // Link to last page, plus ellipses if necessary 
 if ( ! in_array( $max, $links ) ) {
  if ( ! in_array( $max - 1, $links ) )
   echo '<li class="page-item">…</li>' . "\n";

  $class = $paged == $max ? ' class="page-item"' : '';
  printf( '<li%s><a class="page-link" href="%s">%s</a></li>' . "\n", $class, esc_url( get_pagenum_link( $max ) ), $max );
 }

 /** Next Post Link */
 if ( get_next_posts_link() )
  printf( '<li class="page-item">%s</li>' . "\n", get_next_posts_link() );

 echo '</ul>' . "\n";
?>

I need to rewrite the script for Bootstrap 4. Please salt with advice. Urgently needed!