How do I get out of my profile to do my son's taxes now.

You can do multiple returns in the same TurboTax Online account. When you want to start a new return or switch to a previous one, go to Tools > Return Manager > Create a new return.

However, if you want him to have his own TurboTax Online account, click Logout in the top, right-hand corner and then have him create his own account.