Oh yes, I know how to cook using firework. Although it's something I have not done in long time, but I recalled very well how it can done. My personal experience I had with cooking with firewoods was when me and my parents used to visit the our home town during festive seasons. And unfortunately for us, there was nothing like stove or gas cooker for cooking. And for that reason, the only thing we were left to cope with in cooking was firewoods.
I used to assist my mom in gathering firewoods from their sources which is in the bush. She would make sure the firewoods are very dried as logs before they can be conveyed home. Once they are taken home, they will be splited into smaller pieces so that they can give out fire when lited. After this, the splited woods would be put into a chamber where they can be lited, and cooking utensils like pot or kettle will be suspended on the chamber until the food is cooked.
But there is an unforgettable aspect of using firewoods, which is, you have to fan the burning woods whenever they are showing signs of dying down, and this often cause a lot of smoke, and if eventually, it gets into your eyes, it will be unpleasant to them.