When to use it
"Going to" — planned and certain
Use the near future for things you've decided to do — plans, intentions, what's coming up. Maps perfectly onto English "I'm going to…". It's the most natural way to talk about the future in everyday Spanish and accounts for a huge chunk of GCSE marks.
The simple future tense ( hablaré, tendré… ) tends to feel more formal or more distant in time — for "I will" rather than "I'm going to." For GCSE writing, mixing in some near future is one of the easiest ways to show tense range without needing irregular stems.
Model sentence
Este verano voy a viajar a España.
This summer I'm going to travel to Spain.