I did speech therapy both as a child and again as an adult in college. It helped some… then also I removed myself from public speaking types of scenarios, which idk if that’s good, but eventually my stuttering kind of went away because I became less anxious after I grew up and finished graduate school. I took Xanax for a little while, and it marginally helped with stuttering and public speaking. Just a bit. But it’s so addictive and stops working if you take it long term so there really is no solution. I think one thing that might help is doing a meditation practice, it won’t alone solve your problems but it may reduce anxiety in general which usually means your speak more fluently.