Drupal Migration and 404 Errors
To get site working properly:  It seems like .htaccess issue. You do need the .htaccess file. It should be in the document root folder and secured so that any host account can read it. Out of the box Drupal has this file.

To recover Drupal User=1 password: If you are lucky, your ISP may have drush installed globally on this server. SSH to the server and try "drush uli" command. If not, you can try installing drush on your local machine - the pain will be well worth it if you plan to continue working on Drupal. You can use "drush uli" command on your local machine, login with the on-time login link given and change the admin password. They upload the database back to your ISP.