What tense do we use to talk about timetabled events?
The present simple. My plane leaves at 3pm.
What tense do we use to talk about firm arrangements, usually with a time reference?
The present continuous. I’m driving to Portugal to meet my husband later this month.
What tense do we use to talk about something we are (not) planning to do?
Be going to. I’m going to Mercadona after class.