I LOVE GitHub Copilot! I mainly use it for simple stuff that I don't want to remember and I would normaly google. Just an easy comment and let the magic do its thing.
It's also nice if you have to do a lot of repetitive stuff, like if you are refactoring code, and you need to refactor 5 classes for example, after you have done the first, copilot will hint you for the next few classes.
Or a really basic example, when you have some private $variables, and you want to create getters, just say //getters and copilot will create your getters, same for the constructor. Its mainly those things i use it for.
Complexer problems I rather do myself because that way you actually know what you're doing, instead of yeh it works its fine :P