Untitled

We use will to talk about the future when we are not quite sure what is going to happen, so we say what we think will happen.

We use the future with going to when we know with some certainty what is going to happen. And, following this same logic, when we talk about something that we have already decided to do

WILL

GOING TO

promising things and talking about spontaneous decisions

is most commonly used to talk about making plans or intentions.

ej:

I think I'll buy a car

ej:

I'm going to buy a car with my savings