How to Update Database Regular Price and Price in WordPress

This code is used to update your Regular Price and Price in the database, and this code adds your function.php file in WordPress.

<?php
add_action( 'save_post', 'product_price_update' );
function product_price_update( $post_id )
{
 $custom_regular_price = get_post_meta($post_id, '_regular_price', true);
 
 $new_regular_price = get_post_meta($post_id, '_new_regular_price', true);
 $custom_price_add = get_post_meta($post_id, 'addprice', true);
 
 $addprice_new = ($new_regular_price*$custom_price_add)/100;
 
 $update_main_price = $new_regular_price + $addprice_new;
 
 update_post_meta( $post_id, '_price', $update_main_price );
 update_post_meta( $post_id, '_regular_price', $update_main_price );
}
?>