Fill in the correct form of the verb, remember:
Present simple (for future): scheduled events (school starts at 08.20, The restaurant opens at..)
Present continuous: planned events (time, date, place are know and usually confirmed with someone else). We are meeting each other this Saturday at 1 P.M.
To be going to + verb future: I am going to travel to Spain next year.
Future simple (will): (spontaneous decisions, promises about future and predictions without evidence). "You know what? I think I will join you next Saturday")