I tried to insatlling magento2 using composer and git , but both i am getting below error after give folder and file permision
Fatal error: Cannot instantiate interface Magento\Framework\App\Config\Scope\ReaderPoolInterface in /home/magento2/lib/internal/Magento/Framework/ObjectManager/Factory/Dynamic/Developer.php on line 73
If I understand correctly that you have cloned Magento 2 from github and trying to install on CentOS with Nginx..
Please check the branch that you are trying to clone, make sure you are cloning master branch.
If you clone master branch, I am sure you wouldn't experience the below error.
"Fatal error: Cannot instantiate interface Magento\Framework\App\Config\Scope\ReaderPoolInterface in/home/magento2/lib/internal/Magento/Framework/ObjectManager/Factory/Dynamic/Developer.php on line 73"