Hey,
Your server is wherever your domain is hosted on. It is a physical computer usually located in a big datacenter full of other servers.
Your database name is probably not the same as your domain name. Did you setup wordpress? If so you would’ve used the database name while doing so. To check, look for wp-config.php. You can open this file in most control panel file managers and you should see something like define('DB_NAME', '<your_db_name_here>');
Below that should be a similar line for DB_USER which is the MySQL name you’re looking for.
Hope that helps ??