practice of login and signup with database
If you are using xampp then you have to store those file in path xampp/htdocs which mean you have to insert those file in htdocs folder of xampp folder. Go to xampp control panel and start apache and MYsql server. Now goto browser and enter http://localhost/phpmyadmin/ ,this will open localhost database of mysql and create database with utf8_general_ci collation named registation or simply change the database name from the server.php and create table of id,username,password and email.Enter localhost/yourfilename/index.php
If you are using other than xampp go to https://www.google.com/ and search where to insert those file to run in localhost.