You can use the Samsung email app downloaded from the Galaxy app store it's not already on your device it should be when you log in you would simply sync with your outside account sign in with the information you would on your at&t.net account also there might be an app for your specific email provider I use the Samsung app three different email accounts and love it. Once you have the Samsung email app simply tap the settings icon and add your email like the screenshot show likely yours would be under other email
