Student or Learner
I know you are supposed to say to when you are going somewhere. For example, I am going to Washington, DC.
Is it grammatically correct to say going on? For example, I am going on the retreat or I am going to the retreat. Are you going on the retreat or are you going to the retreat?
Both are perfectly fine and grammatical, but on the retreat is more common. Note, it also often ends with a date; e.g., I'm going on the retreat (this weekend).