There are three main ways to talk about the future:
1. a form of "be" + "going to"
3. the present continuous tense
1. "Be" + going to
We use "be" + "going to" for things that we plan in advance.
a. I'm going to the beach tomorrow.
b. He is going to fly to New York next week.
c. They are going to eat salmon for dinner tonight.
We use "will" to answer questions when we don't have to think much before giving an answer. We also use "will" and "won't" to answer questions that are asked using the word "will."
a. Will you doing me a favor? Yes, I will.
b. Will you help me carry this package into the house? Yes, I will.
c. Will you buy me a drink? Yes, I will.
We also use "will" to show commitment.
d. I'll help you put up your shelves.
e. I'll drive you to work tomorrow at 8 AM.
f. I'll be home by 11 PM.
3. We use the present continuous for things that we have already decided to do.
a. I am eating dinner with my mother next Tuesday.
b. Jane is buying a computer tomorrow.
c. We are having friends over for dinner next weekend.