We encrypt all FTP, email and database passwords, so they are not visible as plain text inside your control panel.
The exception is the highest FTP account: this password is visible on the right-hand side when you manage your hosting. You can change all passwords, and changes are usually processed immediately.
Please note: most database passwords will be saved in the configuration or connection strings for your website. For example, for WordPress, the database password is visible inside the wp-config.php file.