There’s couple of things I can recommend, use it to accelerate into building up your core values and worldview which will bring you authentic confidence.
Make a list of guys (real or fictional) that you look up to as confident and visualize yourself being the guy. Think in a frame: what would he or she do/say in this situation? At first it’ll seem to be forced, but you’ll see results and you’ll adapt these behaviors to your personality and it’ll become natural and come from within. You can play these characters as a deck of cards, using appropriate character for specific contexts until you adapt what works naturally for you.
Make a list of all the things you’ve accomplished/good at and return to it every time you need a confidence boost. If you have hard time coming up with things - go smaller and more silly. For example: I’m great at petting cats, I make my mom smile etc.
Learn confident body language and train to stand, sit and walk as a confident guy. Sit in the center of the room. Take up space. Keep eye contact with positive/relaxed/slight smile face. You can see this and other things on YouTube channel Charisma on Command or by analyzing confident movie characters.
Pace your speech, don’t rush to keep attention, use pauses to bring attention, be mindful about your pitch, don’t go high/make your voice crack. Work on a confident relaxed laugh.
In conclusion, don’t overthink it and don’t try to do everything at once. Work on one thing at a time and get used to it.
In a long term - increase your status, but that’s not the ultimate solution. There’s plenty high status guys who are like babies when they see a girl. So work consciously on your character.
Bonus tip that brought me the biggest results - when you’re in a social gathering - imagine you’re the owner of the venue and act towards everyone as a good owner would act towards his guests.
Good luck!