You can't because all Google's apps are not privileged on GOS, so they don't have any permission to do anything remotely like wipe etc. Find my should work fine by itself if you give it location access, it's just a simple location app
that uploads location to Google.
Remote lock is useless anyway, because GOS is not forcing FRP like stock does, so if you lose the device it's possible
to just hard reset it and flash stock.