Here are some things that have helped me. I struggle with social anxiety and feeling "less than" other people. Keep what you think might be helpful and toss the rest.

For me, I've deliberately put myself into situations where I have to interact with other people, an "exposure therapy" of sorts. It's difficult at first and it takes a lot of work, but it's helped me to develop the skills to interact with other people.

A couple of books that have helped me are Feeling Good by David Burns and Maximum Self Esteem by Jerry Minchinton. The first book helps to identify cognitive distortions and challenge self-defeating thoughts. The second one helps to get to the root of how low self-esteem is developed. The book also has some examples of positive affirmations that you can try to sort of retrain your brain. It takes a lot of work, but for me it's worth it.

I have also taken the Meyers-Briggs test and read about the sixteen personality types. Some people are just naturally outgoing while other people are reserved. If you look into it and discover that maybe you happen to be an introvert, you can look into careers that are suitable for people with your personality type. Career counseling can also help.