Many gas appliances can be converted from propane to natural gas, and vice versa. Converting a natural gas grill to propane or a propane gas stove to natural gas are included in this flexibility. Make sure you consult your owner’s manual, look on the manufacturer’s website or contact the company directly. Most grills need some kind of conversion kit.
You should never attempt to connect a gas appliance to the wrong type of gas, as it can be extremely hazardous. Gas appliances are manufactured to be used with only one type of gas, so attempting to connect it to the other gas will not be safe.