In chrome you can change your choice of search engine by opening chrome and clicking on the three horizontal lines found at the end of the address bar. A drop down will appear. Scroll down to settings and click. A settings tab will open up. About half way down is the Search settings. There two buttons. The first is a drop down box where you can set your search engine. (I bet in your case it says Bing!) Change that to Google.
Click on the second button, "manage search engines". Another box opens up. In the top half you can delete all the search engines you don't want by moving you mouse to the end of the name of the search engine - an "x" will appear for you to click which will remove it. The "x" is invisible until you mouse over it - tricky little sucker!
Hopefully this will do the trick. If this is confusing let me know and I will try to clarify more.