sadly, the time to work with this chick was when the problem was first noticed. Some of these are genetic, some are due to trauma- but if the upper beak is really overgrown and the bottom beak is forced off to the side already- there is likely damage to the 'jaw' joint. In mild cases- they can eat ok, in bad cases they slowly starve to death. If this chick is smaller than the others- it is not getting enough to eat, and will eventually starve. Aggressively trimming the beak to an approximation of normal may help it eat, but you will need to do this every few weeks for the rest of it's life. If you can't commit to this, you should give it back to the breeder or dispatch it yourself. The breeder will likely dispatch it if you give it back- it is not a good breeding prospect, nor is it likely to live a normal life without constant support. There are a few living severe cross-beaks out there, but they have very committed owners who work with them. The average chicken owner can't do what they need to survive- and almost all of them starve before they reach maturity- if they are not dispatched prior. The kind thing to do is to end it's life if this is a severe case. Posting a photo may help determine what you have.