Hello!
I am new here but I'm gonna try to help!
I take it this problem is happening on your phone. When you say the guy set up Outlook as your email app, you mean you don't have the google apps (gmail, maps, youtube, chrome, etc.) available in your phone by default?
Sometimes depending on the make of the phone certain apps will be preinstalled. For example, in nokia/windows phone you are going to find that the apps included when you purchase the phone are the microsoft related ones (outlook for mail, bing for searching instead of google, etc.). Unfortunately not every app is made for every operating system, so you may find that apps that you can use on iPhone and Android are not available for Windows Phone.
You may want to see if gmail as an app is available in your phone's "Store" (the app where you look for and download other apps), and then install it and start using it. As you say you are already a google user, you will then need to enter your credentials to sync your account with your phone.

For further help it may be useful to cite your phone's operating system (iPhone, Android, Windows phone).

I hope this helps a bit and does not confuse you further!