What does talk a good mean?

"Talk a good game" is an idiom that means to speak confidently and convincingly about something, even if you don't actually have the skills or ability to back it up.

Here are some examples:

* "He talks a good game about being a great basketball player, but he can't even make a free throw."

* "The politician talks a good game about helping the poor, but his policies don't actually do anything to address poverty."

* "She talks a good game about being a good cook, but everything she makes tastes awful."

Essentially, it means someone is good at *talking* about doing something, but they might not be as good at *actually* doing it. It can be used to describe someone who is boastful or who is full of hot air.