"Will" often suggests that a speaker will do something voluntarily. A voluntary action is one the speaker offers to do for someone else. Often, we use "will" to respond to someone else's complaint or request for help. We also use "will" when we request that someone help us or volunteer to do something for us. Similarly, we use "will not" or "won't" when we refuse to voluntarily do something.
For Example:
1- I will translate the email, so Mr. Smith can read it.
2- I will make you feel better everysay
3- I will give you all you need
4- I will buy the food for you
We use will to offer help to others in the future
USE 3 "Be going to" to Express a Plan
"Be going to" expresses that something is a plan. It expresses the idea that a person intends to do something in the future. It does not matter whether the plan is realistic or not.
For example
1- He is going to spend his vacation in Hawaii.
2- Phuong is going to begin medical school next year.
4- They are going to drive all the way to Alaska.
5- Saul is going to make Phuong's birthday cake.
Those are some examples we use in this case Going to for plans we have in the future it could be for tonight or the next day month or year
if you want to learn more you can watch this video :D
