Click on the three dots on the menu bar. Click settings. Scroll down to search engine. Select Bing from the drop-down box next to search engine used in the address bar. Now, every time you use the address bar in Chrome to search for something you'll get a Bing search result instead of a Google one.

To change the default search engine: Launch Chrome. Click the three-dot menu on the top right. Click Settings. Select Search Engine. Select the engine of your choice from the list of search engines in the drop-down menu. If the browser search engine keeps resetting back to Bing despite that, you'll need to remove the adware or malware responsible.