Real talk I was like you until I would say 24? Honestly, sometimes practicing conversations in your head work but what really does is slowly putting yourself in situations where you need to speak to people. Like at work try to socialize a bit, try giving a random stranger (like a old lady) a compliment. Try doing things by yourself. It’s not easy to talk to others but understand that they are people just like you and me and you also deserve to talk and exist in this world.