yes
That is, what they already do. No kind of fire can burn without oxygen!
yes it is sustainable because when you burn the wood it produces oxygen, and we breath in oxygen.
The air all around you
Wood needs heat, oxygen, and a fuel source to burn. When wood burns, it releases carbon dioxide, water vapor, ash, and potentially other gases depending on its composition.
more space for air (oxygen)
When you burn wood, it is called combustion. This process releases heat and light energy as the wood reacts with oxygen in the air to produce carbon dioxide and water vapor.
Dry wood, fire, ect, oxygen, and a spark are things that are needed for fire to burn.
Adding more oxygen should help
Wood undergoes pyrolysis as it burns. Pyrolysis is the destructive distillation of the wood, producing gasses, which burn as they leave the wood, and carbon, which will also eventually burn. This is how wood normally burns.There is a link to an article on pyrolysis below.
Wood burns indirectly, by adding temperature first the wood will release gasses, which will burn in presence of oxygen. Once it catches fire, the temperature will get high enough to pyrolyse cellulose (main component of wood) and the decomposition gasses burn pretty well !
One way for a fire to burn at a different temperature is it's wood soft wood such as pine burn fast and hot but hard wood such as muscle wood burns slower and cooler but still hot enough to burn you so don't touch it
to get different types of wood and burn them and watch and see which one burn the fastest