What do you mean with “website password”?
Your WordPress installation is just a bunch of files that you can upload and handle via FTP. You’d set your FTP connection details via your hosting provider’s control panel (cpanel).
In the file /wp-config.php WordPress stores the connection details to its database. If you want to change the login details to your mysql/mariadb database, then you’d probably do that via your hosting provider’s panel/cpanel, too.
When you connect to your WordPress site, access to the admin pages and various levels of capabilities are granted based on WordPress user. Here the passwords, etc are stored in the WordPress database.
If you put a “reading password” on a post or a page, then this password is also stored in the WordPress database (and you can have different passwords for every page and post, if you like).
If you need to restore admin access to your WordPress site, then you may need to first add a new admin user in the database.