You can use multisite, but in my opinion this is a complex setup if you are a beginner.
Wordpress is an application that runs on your server. It needs to be installed in a folder, and connected to your database. The only "account" is the one you create inside it once you have it installed.
Unless you are talking about a wordpress.com account?
Let me describe what I think you are doing, and what I think you want. You have Wordpress installed on a hosting account and it is accessible at http://someurl.com
Now you want to use it at http://someotherurl.com -you need to download and install it in this other hosting account. You can put it in a subfolder while you are building the new site, or build it on your local computer. Were you able to follow the tutorial I linked above?