My two cents is that stuttering is essentially subconscious habit and a very high stress that you don’t see because you are in stress , you should visit a hypnotherapist and fix your subconscious or start listening to meditation/hypnosis on YouTube each day one hour before bed(anti anxiety anti stress hypnosis, self esteem hypnosis) after that you should manage and control your speech somehow as well, when you stutter just stop, don’t push, take a breath and release it with that breath from the next part of the word, you should break the habit and update the subconscious. So what you should do: Listen to hypnosis everyday for a month(take some pause then again for a month), after a week or so try to speak with people, call someone but get ready to control yourself you should already see that you don’t panic as much this is what you want, then just build brick by brick the believing,I understand you cannot speak, your subconscious stops you, but as times goes by you should be able to)