Open the door of the wood stove and look at the top-rear of the firebox near the flue collar for the vent. The flue collar is a round piece that connects to the stove pipe.
Look up into the stove pipe for the pipe vent. Not all stove pipes have vents, and they are sometimes difficult to spot. Use a flashlight to help you see. If there is a pipe vent, there will also be a handle on the exterior of the pipe to open and close the pipe vent.
Ensure the vents are open before starting a fire. Open the bypass vent with your hand or the connected lever and turn the handle on the exterior of the pipe to open its vents.