Browser

Okay, so you want a new default or home page on your browser.  That's easy (at least this is what works on my Galaxy S7):

1. Open Chrome,
2. Get the bar that has the home icon, address, number of tabs and the hamburger icon (three vertical dots).  Touch the hamburger icon.  On this menu, touch Settings.
3. On the Settings page, touch Home page.
4. On the Home page page, you should see that it's (a) on, and (b) Open this page is set to "att.net".  Touch the Open this page section.
5. Enter "https://www.google.com " in the field replacing the "att.net".  Touch Save.
6. Then you can return by clicking the "<-" at the top until you're back to the original page.
7. Click the "home" icon on the bar to test.

This question pertains to your cell phone, correct?

If you're using a smart phone, I think all Android phones have the Google App preinstalled. If you don't have the Google App, then download it from the App Store or Play Store. 

If you're on a computer and using Internet Explorer, go to Tools (or the settings icon) > Internet Options > General > Home Page > Enter www.google.com in the box > Apply > OK

On Mozilla Firefox > click the menu icon (three horizontal stripes) General > Startup > When Firefox starts, select Show my home page > Next to Home Page, type in www.google.com 

Safari > settings icon/gear > Preferences > General > Home Page > type in www.google.com

"Google" is not a browser app.  Google is a search/assistant/newsfeed app;.  Chrome is the default browser app on smartphones.  "att.net" is not a browser.  It is the DNS name of a web site.

What is it that you're trying to do?

The hamburger icon has evolved a bit.  When it first came into use, it was a stack of three horizontal lines, and somewhat resembled a hamburger (if you took a lot of artistic license, or were used to hamburgers where the patty is the same size as the buns and the buns were of uniform thickness).  It also somewhat invoked the idea of a list of things (like menu items).  Anyway, that name was given it.  Later styling has shrunk the lines to dots, but the name is still in limited use. Wikipedia remembers.

Glad you're fixed.