The permissions are the Chromium ones.

There is literally no ads nor external SDK or ad-tech or whatever you are referring to (before there was AdMob, but it didn't make much money anyway).

https://reports.exodus-privacy.eu.org/en/reports/com.kiwibro...

The way Kiwi makes money is by partnering with Bing / Yahoo.

You launch the browser, it starts with Bing or Yahoo (depending on your country), and... that's it.

Bing then pays back a revenue-share to the browser each time the user uses the search engine.

The same way that DuckDuckGo gets a revenue-share from Yahoo and Bing too when you use DuckDuckGo.

So, if you prefer Firefox and Google, or Kiwi and Bing, this is just a matter of choice.