Make zoodles using special tool, machine or just use vegetable peeler.
Sprinkle little bit of salt and leave in colander for a few minutes. Then using cheese cloth remove moisture out of zoodles.
Slice onions and peppers in thin long pieces.
Heat the oil in frying pan and add onions and peppers. Cook until almost ready. Then add zucchini and cook for a few more minutes. Shouldn't take long time. It depends how well you want your zucchini cooked. I personally prefer about half cooked.
At the same time heat the oil in the second frying pan. Add garlic and cook for a few minutes. Then add prawns and cook until ready.
Combine prawns with vegetables and cook for couples of minutes more.