Vegan

I think the misunderstanding where it says 'bred to'

By this, they are referring to artificial genetic selection, which you can read more about here: https://en.wikipedia.org/wiki/Selective_breeding

Say we have some species of plant, which makes fruits. If we want fruits that are large, we can take the seeds from the plants that make large fruits and plant them, while discarding the seeds from plants that have small fruits. Over time, we will get larger and larger fruits. However, the fruits might also change in other ways as a result, such as by having a lighter colour or being less sweet.

In this case, they are selecting for characteristics that make a chicken better at laying eggs. Over time, some chickens are better at laying eggs. However, those chickens don't "produce very high-quality meat"