How do I remove DuckDuckGo browser and disable 'Safe search: strict' on my MacBook?

I've had my MacBook for almost two years now and recently, there has been this browser that appears every time I search something up on Safari. It's called DuckDuckGo and it's not something i'm used to. It's also on "Safe search: strict" which is very annoying. I am very sure I did not download it and need help removing it. Thank you :)

[Re-Titled by Moderator]

Original Title: New Browser?