Please answer me in a flewminutes
The burning would cease. Burning in this case is the joining of molecules and compounds that make up the wood (splint/splinter) with Oxygen. If there is no Oxygen available to join, then the splint can’t burn. The same thing would happen if you stuck a burning splint into a jar of pure Helium, Nitrogen, Argon… no Oxygen, no fire.
It’s the same reason CO2 is used in fire extinguishers - the CO2 pushes and keeps the Oxygen away from a flame so the burning thing is cooled off slightly but more importantly is surrounded by a cloud of pure CO2. No Oxygen, no fire.
Yes, there are two Oxygen atoms in every molecule of CO2, but they are bound together very very tightly and stay together - the Oxygen is not “free” or available to join with the hot wood.