CODE EXAMPLE FOR PHP

run drush command from php

<?php
exec('/usr/bin/php /var/www/drush/drush.php site-install --yes --db-url=mysql://USER:PASSWORD@localhost:3306/DATABASE --account-name=DRUPAL_USER --account-pass=DRUPAL_PASSWORD --account-mail=contact@email.com --site-name=SiteName');
?>
  
you can also try this also.
  
<?php
  exec('drush site-install --yes --db-url=mysql://USER:PASSWORD@localhost:3306/DATABASE --account-name=DRUPAL_USER --account-pass=DRUPAL_PASSWORD --account-mail=contact@email.com --site-name=SiteName');
?>