How do I edit text in a grouped layer?

The "<Group>" layers in your screenshot are simply Illustrator groups which got rasterized / flattened, and are only editable as pixels and not dynamic objects anymore. They only have the name of "group", but are not actual groups. The groups in Photoshop are the "CAT", "Layer 10", etc, with the little Folder icon that these layers are nested under. This doesn't change your situation though.

If the text is rasterized as it looks like, your only option is to delete it, and try to replicate it with the same font using the text tool.

You can also try Generative Fill, select the text (and a sufficient area around it) and prompt it to replace it with one specified by you. You can try different models to see what works best. Firefly Image 5 does a better job with text.