look I'm not an expert, but try to do it all over again, save only the language, in case you don't use English. redo the database. here it is working fine. Also see this question:
Before install, Your server must match following requirements to run the script properly
PHP 5.6.0+
OpenSSL PHP Extension
Mbstring PHP Extension
PHP Fileinfo extension
PHP Zip Archive
PDO PHP Extension
XML PHP Extension
JSON PHP Extension
Rewrite Module (Apache or Nginx)
Please consider that some other php setting values might be required.
PHP.INI Requirements
open_basedir must be disabled
File and folder permissions
/includes/config.php 775