You might want to do some singing exercises that are fun, use speech, while at the same time are not frustrating. There are apps for singing along with popular music or just listening and singing with your favorite music. You will be fluent and it might help your confidence a bit. Have fun with it. Historically Ed Sheeran, Carly Simon, BB King, Mel Tillis and other singers have been stutterers. An adult friend of mine is a salesman and while he still has a mild stutter at times, he has dramatically improved it by keeping a beat with one foot to maintain fluency. It is not at all noticeable.