Advanced Custom Fields deleting some code and adding code for a slider

Your question is not very clear, but as I understand you want to place ACF field on your pages. You can edit custom field in Custom Fields, choose desired field group and custom field and simply edit it.

If you want to create new field and place it on your page just use this in function.php

function function_name( $atts ){
    $picture_name = get_field( 'field_name' );
return $function_name;
}
add_shortcode( 'your_field', 'function_name' );

And place shortcode [your_field] on page. Or use it directly in template with <?php echo get_field( 'field_name' ); ?>

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