So, to check my localhost, this is the page I get: IIS7
If you look at the bottom of the page of:
How to set up a local testing server for Dreamweaver
It looks like you have IIS running at the same time you are trying to use Apache so it is always going to be busy.
You need to setup a local testing environment to learn how to work with a database and PHP. Then you can tackle getting it to work on your hosting company's server.
The connection file for your local testing environment is going to be different than the one you use for the hosting company. Your host is telling you that they don't allow you to access their database server from outside the server. That's fine. You test on your local machine using your test environment, and then transfer everything to the live server.