Can I say "we're gonna talk about" instead?

In what situation do you use the phrase "in itself"?

"In itself" is a phrase that means it's considered separately from other things, considered alone. This is a shortened version of "in and of itself." You can use this phrase when you want something to be emphasized on its own. Ex: In itself, it's not a hard task, but when you combine all of the other tasks, it's much harder to accomplish. Ex: One cat is a lot of work in of itself.

What does "in a nod" mean?

The phrase "in a nod" is used when someone is aware of or wants to recognize the influence or importance of something. It means to show recognition, acknowledgement or consideration. I'm this made it means that this new government plan is because the government has been considerate to small businesses. Ex: The dress is designed as a nod to old Hollywood glamour. Ex: The title of movie is a nod to the original book.

What does "It’s over between us" mean?

"Something is over between A and B" is a common expression that means something between A and B is finished and not being continued. Therefore, "it is over between us" means that the relationship between you and me is over. Here are some examples of it being used in different sentences. Ex: It's all over between him and me. Ex: It's over between us. We are history. It can be also used in a way that does not refer to a relationship. Ex: The corporate spat is over between Google and Amazon. Ex: The fight is over between Paul and Sarah.

I assume "region" has a similar meaning as "area", "state" or "county, but is it commonly used in reality as well?

You're right about the meaning of "region"! From what you've mentioned, the closest word to it is "area". And yes, it is commonly used in reality too! Ex: There was a lot of flooding in the northern region. Ex: I've never been to that region before.

In what circumstances can I use the word "indeed"? Can you show me some examples?

The word "indeed" is usually used to show agreement with a previous statement that was made or to emphasize a point. Ex: Indeed, it is a hot day. Ex: She is smart indeed.