[new_guy]

Something no-one else has mentioned yet is learning methods. Stuff might not be sticking because you're using the wrong learning method for you. Instead of reading a book, maybe watch a video tutorial instead, learn by doing etc, get a mentor to pair program with?

Also look up 'imposter syndrome', it does sound a lot like you're suffering from self-esteem issues too so maybe get someone to talk with?

[throwaway88p]

Interestingly, I've never been a fan of video tutorials in the past, but have tried using them in the past weeks. There are some aspects of it I like. It's easier to keep attention with a video than a large wall of text these days (though it used to be the opposite). Unfortunately, it's not so easy to skip around content in a video, for example to avoid useless filler content or to return to a small chunk of content to review.