I made duck duck go my brwser..how do i change back to safari

No, your browser could be Safari, but there is no Safari search engine. If you have changed your search engine choice to DuckDuckGo, that is fine, and it is a good, non-tracking search engine.

Change Search settings in Safari on Mac - Apple Support

I switched to duck duck go and now I am having all sorts of trouble. I want to uninstall. I have much on this topic in the Q & A, and tried to implement suggestions, but still cannot get rid of it. When I go to Safari to choose preferences that does not appear in the drop down menu. If I go to extensions in the drop down menu and check uninstall it says undo the privacy check mark I did that and still cannot uninstall.

I can't say for sure but with the browser I use I can go to Preferences and one of them tells it to use that broser as my default browser.

Are you attempting to change your browser or your search engine?

additional information for my post above. I found DuckDuckGo Privacy for Safari app in my applications, but cannot find anything in the drop down menus or tools bar.