Sorry to hear about your chick.
Can she bear weight on the leg and foot?
The green is bruising, but it would be hard to know if it's broken or just sprained. If you have vet care, that's always best.
If you don't have a vet, then you can gently wrap or splint the foot/leg to help support it. Take great care that wrappings are not too tight and cut off circulation and check them frequently.
Here's info that you may find helpful
https://theiwrc.org/wp-content/uploads/2011/05/Duerr_Splinting_Manual_2010.pdf