Present Continuous - future arrangements; often with time, date, place
- I am going to a wedding on the 24th of October 2024.
Present simple - schedules, timetables
- The bus leaves at 10 am. / English class starts in the 7th hour.
Be going to + infinitive - future intentions, plans = already decided to do smth & you tell people about it (think NY's resolutions)
- I am going to work out twice a week.
WILL + infinitive - spontaneous decisions & predictions
- I think I'll have a coffee. / It will snow tomorrow.