Why you need to Update Core WordPress?
WordPress is vulnerable and these core updates are really important so if your website is specially an eCommerce website you should update your WordPress on daily basis. You also need to make sure that all the plugins and theme are compatible and there is no controversial plugins which can conflict with the upcoming WordPress versions.
How to enable force auto update.
To Force WordPress core to update automatically the steps are really simple if you are familiar with FTP transfer or Filezilla.
Access to wp-config.php file which you can found in the WordPress directory in your web server, then open it using Notepad or any text editor you use, then add the following line.
define( 'WP_AUTO_UPDATE_CORE', true );
TIP: You can add this line next to WP_DEBUG line.
save the file and upload it. Now for next time when the WordPress has any update it will automatically update your installation to latest version and you will receive an email, once you get it make sure everything is working fine on both ends.