To change the default search engine in Safari, follow these steps:

• Step 1: Open the Safari browser and go to the Safari menu in the upper-left corner.
• Step 2: Select Preferences from that dropdown.
• Step 3: Once the Preferences window pops open, click the drop-down menu next to the Default search engine.
• Step 4: Click on the search engine you want to make your default. You can choose either Google, Yahoo, Bing, Ecosia, or DuckDuckGo.

This will change the search engine that is used when searching from within Safari. However, Siri and Spotlight will still use Google as their default search engine.