wcraq_quote_fields.php

<?php
/**
 * Add extra fields to quote form
 */
function prefix_add_quote_fields( $fields ) {
  $fields['province'] = array(			// Update the key here
		'type'        => 'text',	// This will add a text field
		'label'       => 'Province',	// Update the label here
		'required'    => true,		// Set whether this field is required
		'placeholder' => 'Province',	// Update the placeholder text here
	);
  return $fields;
}
add_filter( 'wcraq_quote_fields', 'prefix_add_quote_fields' );