Were I in your shoes, I would make a game of making mistakes, seeing how many times you can "try" to be wrong? Reward yourself if you are afraid, answer/try whatever and get it wrong! Laugh at being wrong (replacing the fear of being afraid) and keep score, how many times you get it "right" when you think you're right versus how many times you actually get it "wrong". But you have to play to win (Maryland's Lottery slogan) no just doing it inside your head/imagination. Your imagination is what's getting in your way, you imagine what it will be like to be wrong. So, use your imagination to help you instead. You cannot know the future (whether what you say/do will be right or wrong for you/what you want in your life) so give that up and just go with your best guess.

For me, there was a lot beyond the fear, if you do something you are afraid of it can be unfamiliar territory and wholly unpredictable and like being on thin ice, much more scary than just holding back on your head's shoreline. Remind yourself how quickly you can "shut down", your body takes care of you so you can take a chance because if it gets too much your body will shut down. The ones you get "right" will move the borders out further so you have more room and are less afraid. Eventually the rightnesses and your practice/ability taking care of the wrong ones will be greater.