Talking about future plans

Albert- Hi Arnau!! What are you doing on Saturday evening? Are you free?
Arnau - No, I'm not. I'm busy.
Albert- What are you doing?
Arnau - I'm going to Andreu's house. Do you want to come?
Albert- Yes, thank you. It's a good idea!!
Albert - Ok. At 7 o'clock in Andreu's house.
Arnau- Bye, bye!!