Do eggs change through metamorphosis into something quite different?

No, eggs do not undergo metamorphosis into something quite different; rather, they develop into a mature form of the same species. For instance, a bird egg will hatch into a chick, which is a young bird, and eventually grow into an adult bird. Metamorphosis, as seen in insects like butterflies, involves a complete transformation from one life stage to a distinctly different one, but this process is not applicable to all egg-laying species.