The honest answer to "what's the best martial art for a beginner in Dubai" is: it depends what you actually want. Pick by goal, and the choice gets easy.
If you want self-defense, fast
Start with Krav Maga. It was built for real situations, uses instinctive movements, and gives beginners usable capability within weeks rather than years.
If you want fitness and to learn striking
Boxing, kickboxing or Muay Thai. All three are superb conditioning, build real striking skill, and are genuinely fun — which is what keeps beginners consistent.
If you want ground skills and problem-solving
Brazilian Jiu-Jitsu teaches you what to do if a fight goes to the floor, and rewards technique over size. It's a deep, addictive skill, though most real threats start standing.
If you want all of it
Train a system that integrates them. Most people who start with one discipline eventually wish they'd built the others alongside it.
What to look for in any beginner programme
An assessment before you start, small groups so the coach actually sees you, controlled pressure-testing so the skills work for real, and coaching that scales to your level — you should never need to "get fit first." At DKing Combat System, coached by DKing Saad in Al Quoz, beginners start across these disciplines inside one application-based system, so you build real-world capability from day one instead of just collecting techniques.