In fact, you open a Google account and then open a Google Analytics account and set up the Tracking Code that you add to your website.
To explain in a little more detail,
You can open your account after clicking the Sign Up button in Google Analytics. Then you will press the Start measuring button that appears on your screen and you are good to go.
The next thing you need to do is account set-up. To do this, you will start by entering the name of your website.
After entering the remaining information, you will press the create button.
In short, you have created your Google Analytics account.