In most modern gas ovens, there is no separate external switch or button to turn off the oven without opening it. Typically, the oven is controlled by turning the knob to the desired temperature or setting, and to turn it off, you would need to turn the knob back to the "Off" position. This requires physically accessing the oven and interacting with the controls.
If your oven is designed with a digital control panel, it might have a "Power" or "Off" button that you can press to turn off the oven without opening it. However, even with a digital control panel, it is generally not recommended to completely turn off a gas oven without first verifying that the pilot light or electronic ignition system has also been deactivated.
Keep in mind that safety is paramount when dealing with gas ovens. If you suspect a gas leak or encounter any issues with your oven, it is essential to shut off the gas supply to the appliance and contact a qualified technician for inspection and repair.