When protection will not turn on.

Turning it on asks for three separate iOS permissions in a row: a VPN configuration, a content filter, and Screen Time. If one was declined, the shield will not seal.

Go to Settings › Shield in Bramble and run through it again. Anything missing is named there.

The Safari extension is separate

The Safari extension is the one piece no app can switch on for you. It lives in iOS Settings › Apps › Safari › Extensions. The Safari steps go through it screen by screen. If its switches will not move, see when the Safari switches are greyed out.