You must use the Future progressive tense to indicate an action which is ongoing at some defined future moment:

At this time next week I'll be lying on the beach in the sun.
Look at the queue! We'll still be waiting at 6 o'clock at this rate.
I'll probably be working when you call tomorrow so just leave a message on my phone.

It is used, strangely, to indicate a probable progressive action for the present moment:

You want to see Morgan? He'll be unloading the truck I think. Have you checked the stores?
Jane left Paris six hours ago. She''ll be landing in New York any time now.
What's the weather like at your end? I suppose it'll be raining, as usual.

Sometimes it is used colloquially for a future action for no very good reason.

Instead of:
"I'm leaving at midnight." or "I'm going to leave at midnight." or "I'll leave at midnight." (all of them correct)
you are quite likely to hear: "I'll be leaving at midnight."

Instead of:
"I'm seeing John tommorow." or "I'm going to see John tomorrow." or I'll see John tomorrow. (all of them correct)
you may hear: "I'm seeing John tomorrow."

In the exercise, use the future progressive to fill in the gaps using the verb in brackets at the end of each sentence. Other forms are correct grammatically but are not allowed here.

You can use contractions when appropriate but don't forget the apostrophe: 'm 'll etc..