Upgrading Drupal

Hello,

what I'd like to do is to transfer the Articles from a Drupal 6 into Drupal 8.

I have admin privileges on both Servers and both MySql dbs.

The easiest way would be through SQL code.
I analysed the DB on Drupal 6, but on Drupal 8 there are many differences.

Before I go on searching and trying I find it wise to ask the community if there is something already in that directions and of general ideas.

All articles are written by same user, the only thing to take additionally care of is that there exist tree menus.

Does anyone know how to fix the following PHP Fatal error?. I am trying to upgrade Drupal837 to Drupal853 using drush.

php version: PHP 7.2.2

Error:

PHP Fatal error:  Uncaught Error: Class 'Drush\Config\Environment' not found in /var/www/html/vendor/drush/drush/drush.php:58
Stack trace:
#0 /var/www/html/vendor/drush/drush/drush(4): require()
#1 {main}
  thrown in /var/www/html/vendor/drush/drush/drush.php on line 58
 

   The site was Drupal 5.3.3, now update to 8.5.3, it finish the update, but can not open the site, it instantly show this error message from home page

    I can not find the answer anyway, please share your experience, thanks.

Hello everybody,

sorry if my english is not very good !

I have upgraded manually on local site from drupal 8.3.5 to 8.5.3.

After updating the database, i have an error :

Hello everybody,

sorry if my english is not very good !

I have upgraded manually on local site from drupal 8.3.5 to 8.5.3.

After updating the database, i have an error :

I don't want to upgrade to Drupal LTS. Due to financial constraints I'm very happy with my D6 sites.

I just want some patch code which I can add in the bootstrap.inc to mitigate or do away with this vulnerability. Or can anyone explain me more about this so that I can myself make some code and add it