To make sure your profile is hidden from others on the Community stream, please go to your Profile (small icon of your profile photo in the top right of your screen) and you will see a toggle 'Show me in the Community' that you can disable if you no longer want to be visible to others on the Community stream.
Please note that other members will still be able to find your account through the references you left on somebody else's profile or if you join a Language Party.