Nobody at work is developing me. What do I do?
First, you have to take some responsibility for your own development.
Ask for more.
If you're doing your current job well and you're ready for another challenge, say it. Ask your supervisor, "Is there anything I'm doing right now that I need to improve? Because I'm ready to learn something else."
But be prepared for an answer you may not like.
If they tell you you're not ready, stop and do a self-inventory. What mistakes have you made? Are there things you still haven't mastered? Maybe you made a mistake six months ago that you're already past, but the people responsible for giving you more responsibility haven't forgotten it yet.
That takes time to overcome.
Stay consistent. Be dependable. Keep producing good work. Eventually an opportunity will come along where you can demonstrate that you're capable of more, and one successful opportunity can change how people see you.
There's another side to this too.
Sometimes the company really isn't developing you. Sometimes the people above you are busy, the schedule is tight, or you're working for somebody who isn't particularly good at teaching. I've been in situations where the answer was basically, "I don't have time to teach you this right now. Do it this way and I'll explain it when I can."
That's reality sometimes.
But "later" can't become forever.
If you've demonstrated that you're capable, you've communicated that you want to develop, and nothing changes over time, then you have to decide whether your goals and the company's opportunities still line up.
Nobody is going to care about your career as much as you do.
Ask for the opportunity. Be ready when it comes. And make sure your current performance gives people a reason to give you the next one.