How to apply the dkpdf_pagebreak_shortcode function ?

Hi I need two columns in the pdf, but i don´t know where is the location correct for apply the next code:
[dkpdf-columns columns=”2″ equal-columns=”true” gap=”20″]
[/dkpdf-columns]

or where call to the function dk-pdf/includes/dkpdf-shortcodes.php, this is the code:

function dkpdf_columns_shortcode( $atts, $content = null ) {

$atts = shortcode_atts( array(
‘columns’ => ‘2’,
‘equal-columns’ => ‘true’,
‘gap’ => ’10’
), $atts );

$pdf = get_query_var( ‘pdf’ );

if( $pdf ) {
$columns = sanitize_text_field( $atts[‘columns’] );
$equal_columns = sanitize_text_field( $atts[‘equal-columns’] );
$vAlign = $equal_columns == ‘true’ ? ‘vAlign=”justify”‘ : ”;
$gap = sanitize_text_field( $atts[‘gap’] );
return ‘<columns column-count=”‘.$columns.'” ‘.$vAlign.’ column-gap=”‘.$gap.'” />’.do_shortcode( $content ).'<columns column-count=”2″>’;
} else {
remove_shortcode( ‘dkpdf-columnbreak’ );
add_shortcode( ‘dkpdf-columnbreak’, ‘__return_false’ );
return do_shortcode( $content );
}

}
add_shortcode( ‘dkpdf-columns’, ‘dkpdf_columns_shortcode’ );

Thank you, greetings!

The page I need help with: [log in to see the link]