There are various ways to get to your Google account.
Some are to get to your email (if you use Gmail) either in the email app or the browser.
But in order that you can do all the Googley stuff you need to log into your account. You can either do that through 'settings' then add an account, or by firing up the Play Store and entering your details. Since you've tried the settings route, have a go through the Play Store and see if that works. Failing that, try logging into YouTube, which also uses you Google account.