Connect to MySQL Remotely

[Hello World]

GRANT ALL PRIVILEGES ON *.* TO USERNAME@IP IDENTIFIED BY "PASSWORD";

Server A: MySQL
Server B: Connect to Server A MySQL

Username: Is this PSA username (admin), database username, root, or username of virtual hosting account?

IP: I believe this is the IP of Server B. I wonder if I could use Server B's hostname instead of IP.

Password: Is this the password PSA's control panel, database password, root password, or password of virtual hosting account?

Thanks in advance.