For installation of extension 

• Log in the ftp, and then go to the Magento 2 root folder (generally present under the public_html folder).
• Create a new folder named code under the app folder; under code folder, create a folder named Ced.
  1. Upload or Drag and Drop app/code/Ced directory.
  2. After successfully uploading the directory, the extension will be installed/upgraded.
  3. Now run the  following upgrade command in cmd
            php bin/magento setup:upgrade
           php bin/magento setup:di:compile
          php bin/magento setup:static-content:deploy -f
          php bin/magento index:reindex
         php bin/magento cache:flush