It doesn’t need vented. As another poster said, houses aren’t airtight enough to allow the stove to consume the oxygen in the house.
If you’re concerned, get a carbon monoxide detector. If the stove starts depleting the oxygen levels in the house, the stove will begin to burn inefficiently and create carbon monoxide and trip the alarm long before you reach a dangerous condition.
If you’re STILL concerned about it, just crack a window when you cook.
Just so you know, my mother and grandmother both used gas cooktops for many, many years with no ill effects.
It does't need to be vented either.