Hi, Marcos, Hi, Marcos,

How are the things going? How are the things going?

you don't need to use "the" when saying "things" - just "How are things going?"

How are the things going? How are things going?

How are the things going? How are things going?

How are the things going? How are things going?

This is a set phrase.

I have've just received your email. / I just received your email. I've just received your email. / I just received your email.

In general, using contractions is informal and not using contractions is formal

I have just received your email. I just received your email.

Is it true that we aren't going to take part join the basketball competition? Is it true that we aren't going to join the basketball competition?

'take part in' is a fairly formal way of saying 'joining', for an informal email 'joining' is fine

I couldn't be more enragedadder. I couldn't be madder.

Again, 'enraged' is not very fitting for an informal email to a friend.

I couldn't be more enragedany angrier. I couldn't be any angrier.

"Enraged" is a bit too formal of a word

I couldn't be more enragedangry. I couldn't be more angry.

We don't really use the word "enrage" in the US.

My parents have tried to cheer me up, but it hasn't worked out's not working. My parents have tried to cheer me up, but it's not working.

I need him to tell me the reasons why we are getting benched. / I need him to tell me why we're getting benched. I need him to tell me the reasons why we are getting benched. / I need him to tell me why we're getting benched.

I needwant him to tell me (the reasons) why we are getting benched. I want him to tell me (the reasons) why we are getting benched.

need vs want → You'll live if he doesn't tell you why.

If I were you, I would do the same. / I'd do the same if I were you. If I were you, I would do the same. / I'd do the same if I were you.

Anyway, Iit's getting late. Anyway, it's getting late.