Practicing positive self-talk can help you build your confidence; you must practice doing it.

You can’t be putting yourself down all the time if you do that, then you're never going to have any confidence in yourself since your brain will think against it. How can you fix this? Give yourself a pep talk. It might sound dumb but if you try lifting yourself up in front of the mirror you might just have more energy to try and make yourself better for the next day.

It’ll also let you see your slow progression in getting more confidence. Talking to yourself trying to get hype for what you have achieved and how happy you can be boost confidence in a very nice way. I used to feel uncomfortable with my body and how I look like, but since I started practicing self-talk and being positive everything has become easier for me. I feel more happy, comfortable, and confident with who I am.

Self-talk is very positive, you just have to start practicing it in order to feel better and hype yourself and what you've done and your confidence.