We use the future continuous, or the future progressive tense, when we indicate some moment in the future (like "when you come" or "at ten o'clock tomorrow") and we say that at this moment there will be some activity going on. This activity will start earlier in relation to this future moment and it will go on after it.
At some moment in the future, I'll be in the middle of doing something.
When the boss comes in the office room, everybody will be sitting at the desks and working hard.
At this time tomorrow, I won't be sleeping. I'll be packing my suitcase.
When we arrive at Sarah's place to pick her up, she won't be ready to go. She'll still be choosing which dress to wear.
In the next episode, we'll be exploring the most beautiful places in Cornwall.
How to form the future continuous
The future continuous tense is formed by the auxiliary verb "will be" and the main verb with -ing ending.
will be + infinitive + -ing
|will be ('ll be)
You can read more on how to form and how to use the past perfect in the related topics.