If the beak is just broken and the soft tissue is not damaged too much, it may grow back, but will take time. If the entire top is missing then it probably will not grow back. (I can't tell really from the picture). They can often adapt remarkably if you give them time and support. Important to keep it as clean as you can and make sure she can eat and drink. Monitor her weight and either hand feed or tube feed (https://www.backyardchickens.com/threads/updated-go-team-tube-feeding.805728/) if she is not getting enough to maintain weight and hydration until she figures it out. Making a mash by mixing water into her regular feed, so it's like thick oatmeal, will make it easier for her to scoop with her lower beak. Raise feeders and waterers up to shoulder height to also make it easier for her to scoop. She will be unable to peck at things on the ground and pick them up. Here is a link to a thread (maybe the one mentioned above?) with a very similar injury, pictures after recovery are in post #28. https://www.backyardchickens.com/th...nd-the-top-part-of-her-beak-came-off.1171668/
