Tensing up while speaking! And Just enjoying life

Tensing up while speaking! And Just enjoying life 18(Y/O) M Basically , Everytime I talk , I just tend to tense up my abdomen and shut my vocal cords (like I stop breathing), regardless of whether I stutter or not , it just happens , most of time , I stutter when I do this. Whenever I speak few fluent sentences in between my stutterered speech , this behaviour doesn't happen.(effortless) This tensing up makes my every convo very uncomfortable and unenjoyable , I seem to be nervous , and I repel every other person , they seem to think that I dont wanna converse, when in reality I do . I wanted your opinion on whether this behaviour is learned or is it just the way our brain s neurology is and tell us to do this. Cuz I feel like it to some extent is learnt Basically, my point is that I wanna speak (stutter) effortlessly. How do I do it ? Also now me being 18 year olds already , I wanna leave stutter behind and just enjoy my life , get the most of it , I'm really tired of being depressed , frustrated of something I can't control. I feel like I'm missing many things that life has to offer , e.g relationships , social life , having friends and overall just being happy generally . I might regret not doing these things when im like 60 , my life is so dull right now. I'm tired of being lonely and sad all the time. I feel drained. Any uplifting stories ?