Not everyone is smart or has special skills, but skills can be learned and so can self-confidence. What I'd worry about is your habit of blurting out offensive comments. While you can work hard and apply yourself, rude and inconsiderate behavior will hold you back. Work on that as well as showing up every day with a good attitude ready to give your 100% to whatever task you're applying yourself to. Flipping burgers or cleaning toilets are both honest jobs that should be applauded, for example. Whatever job you're qualified to perform just put your full effort into it and be proud of yourself.