I have noticed the way people greet each other has changed. Could you please tell me how I should respond to the following greetings?
1. How are you doing?
2. How is everything?
3. How is it going?
4. Hi there.
5. How is your day?
6. Good luck ( used to mean Goodbye).
Looking forward to hearing from you.
Thank you in advance.
I think anything, though 'fine thanks, and you?' might sound a little formulaic and stilted.