Brave browser is on iOS, but I don’t believe its adblocker extends to Safari.
Not being able to set a default browser on iOS tends to make you use Safari more than another browser you have installed since tapping a URL in another app will open Safari, unless that app supports setting a default browser, which not many do and even fewer support opening Brave. It has to be implemented on a per app basis since they’re really just using the x-callback-url scheme. Most tend to only support setting Safari, Chrome, or Firefox.