I have upgraded from Magento 2.3.6-p1 to Magento 2.4.0 all went well regarding
composer update
bin/magento s:up
rm -rf var/cache/* var/page_cache/* generated/code/*
bin/magento s:d:c
bin/magento s:s:d -f
when trying to access the site it shows the below error both on the frontend and admin panel.
Fatal error: Declaration of LaminasServiceManagerServiceLocatorInterface::get($name) must be compatible with PsrContainerContainerInterface::get(string $id) in /home/techhopc/mysite.com/vendor/laminas/laminas-servicemanager/src/ServiceLocatorInterface.php on line 16
