Going to and Present Continuos as future.

We use going to talk about future intentions, ambitions or unfinalised plans.

•  We're going to visit Europe this summer.
•  I'm going to study Economics at University.

We use the Present Continuous to talk about a definitive plan in the near future. We usually mention the time or /and place as well.

• We're flying to London in five hours.
• We're visiting Buckingham Palace this afternoon.