We can use both forms to express predictions in the future. The biggest difference is that be going to expresses a plan that the speaker made before the conversation. Will shows a decision that the speaker makes at the time of speaking.
Consider this situation:
Terry, would you like to come to my house for dinner tomorrow night? I am going to have a dinner party. I am not sure what dessert to have…. Oh I know, we will have chocolate ice cream sundaes!
Je tiens à remercier Le Carrefour des langues. Le formateur avec qui j’ai le plaisir de travailler a su adapter conversation et règles grammaticales de façon à faciliter l’apprentissage. La Direction a été à l’écoute de mes besoins et de mes disponibilités et m’a proposé un horaire selon mon emploi du temps.
Gaétan
Garde côtière canadienne