Sometimes even after running php bin/magento setup:upgrade command module don’t get install , in this case first enable the module via

php bin/magento module:enable Excellence_Module

Once done follow the steps below to install Module :

  • Run php bin/magento setup:upgrade in ssh in folder root of magento 2
  • Run php bin/magento cache:clean in ssh in folder root of magento 2
  • Fix the permission of var/ folder (Run chmod -R 777 var/ in ssh in folder root of magento 2)