As a kid I was a moderate to severe stutterer and what helped me the most besides speech therapy. Was joining BJJ and grappling. That gave me confidence I didn't have before and it helped me relax so so much. I felt like I walked around without the tension I normally have in my body just cuz I was always so nervous about stuttering. My stutter almost totally vanished; since then I have stopped grappling due to college and there being no gym near me. And not saying that's the only way. But it was a hard physical hobby that I didn't have to speak at all if I didn't feel like it and I could build confidence and be proud of something that didn't have to have any speaking at all if I didn't feel like it. That helped a ton and I plan on starting as soon as I can again. Edit: also fighting people as a hobby feels pretty "masculine"