“Will and be going to” are the words to form the Future Tense. The words are to express something happens in the future.
However there is the different in using the words:
Will is used to express a promise or something that will happen if something else is done. Examples:
I will come to your house next week.
I will come to your house if you invite me.
Be going to is used to express a plan. Examples:
I am going to spend my holidays in my Grandpa’s house.
I am going to come to your house when your mother is out.
That’s all from me, and as usual, if you have your own opinions, please share with us here.