Windows 10 has Cortana doing all the searches for you, not only anything indexed locally on your computer but also stuff over on the web as well. When doing the search on the web with Cortana, it uses Bing as the default search engine and it cannot be changed. If you are not the Bing person, here is a little trick that lets you change this default behavior.
First of all, install and start using Google Chrome if you haven’t done so. If you are in love with Edge, you will have to stick with Bing. Simply head over to Google Chrome page and get it installed on your Windows 10 computer.
Then, make the Chrome as your default browser. To do so, open Settings app, go to System and Default apps, scroll down to see web browser section, and change the default browser to Google Chrome.
Now, add this Chrome Extension called Bing to Google to your Chrome, and you are all set.
From this point on, any search typed in Cortana will be redirected to Google search in Chrome browser.
If you prefer using DuckDuckGo or Yahoo as your default search engine for Cortana, you can use this extension called Chrometana instead. It will ask which search engine you want to choose to redirect from Bing when it’s added to your Chrome.