I am going to be a doctor when I finish university. (prediction)

Jack is having a dinner party next Saturday. (events which have been planned for the future)

I haven't made any plans for Easter. I will probably stay at home. (They're not sure what they will do)

Peter knows that he is going to fly to Chicago next week. (future plans)

Oh no! I've broken the vase. I will say that Nemo broke it. (Use the future with "will" when reacting to something that happens at that moment)

I will be studying at nine tomorrow evening. (use the future continuous to express what will be happening at a specific moment in the future.)

John hasn't eaten. - Don't worry I will make him a sandwich. (Use the future with '"will" to react to a present situation.)

Unless he arrives soon, we will not go to the party. (Use the future with "will" in first conditional sentences)

Do you think you will get married before you're 30? (prediction)

Look at those clouds! It is going to rain! - Use the future with "going to" when you can see that something is about to happen.

I'm going home. I'll see you tomorrow. Bye! (they just decided)

I am meeting my friends at the cinema after work tomorrow. (fixed plan)

I am flying to London tomorrow night. (fixed plan)