What do you do when you never had confidence when you were young and still don't have confidence as an adult?

Do things to give yourself confidence like sticking at things and succeeding in them. Work out, keep doing things you're interested in and you'll naturally get good at them and have more sources of confidence. Realise that everyone else is just another person who holds no more value than you do and what you interact with is just the social faces of others, they won't show you their insecurities so don't compare yourself.

Do something that interests you that’s also difficult because you don’t feel comfortable and confident with it.

Dont give up at it. People with low confidence have a low value of themselves and will always listen to that negative internal dialogue.

Confident people don’t let anyone hold them back, especially themselves, laugh off failure and embarrassment. The only way to learn how to do that for yourself is to force yourself into those uncomfortable situations until you can figure out how to change that internal dialogue.

My confidence kind of different from young to adult when younger I was more confident at talking I was very good at communication but scared going places by myself I was ok with relationships I would be in one but had to take tablets when younger for my nerves now I have learnt to go places by Myself doing more by myself but I don’t know I find hard to talk sometimes not all time but most my confidence slightly different in a way but not how should be compared to most still learning myself

Maybe you should simply learn how to not give a damn.

It's like building a house bit by bit also think positive and also remember
He or she who never made a mistake done nothing