You have a few options. If you only need to block ads in a browser, just use Firefox and make use of the uBlock Origin mobile add on (Chrome doesn't support add ons for mobile) If you want systemwide ad blocking, you can either use an app like DNS66, or if you have root access, an app like AdGuard (the better option)

As for the face unlock, it uses a different API than the fingerprint unlock, and almost no apps have support for that yet. It was a huge mistake IMO because now you have to wait for them to roll out support, and in the meantime, you're stuck with just using a PIN. Why they would remove the fingerprint scanner without giving apps time to integrate the new face unlock API makes zero sense to me