How convert kWh to W
If something uses N kWh in a 30-day month, has an average consumption of

$$N \frac{1000\text{ W/kW}}{720\text{ h/month}}\text{ watts}$$

In other words, to convert "energy" to "power", divide by "time".



Just as an example, suppose you use a 1500 W toaster for 3 minutes to make toast for breakfast. That would be a total of

$$1500\text{ W}\frac{3\text{ min}}{60\text{ min/hr}} = 75\text{ Wh} = 0.075\text{ kWh}$$

of energy. If you do that every day for a month, the total energy would be

$$0.075 \cdot 30 = 2.25\text{ kWh}$$

The average power of the toaster over the entire month would be just

$$2.25\text{ kWh} \frac{1000\text{ W/kW}}{720\text{ h/month}} = 3.125\text{ watts}$$

as compared to its peak power of 1500 watts.

In other words, a 3-watt alarm clock, which runs continuously, costs you the same amount in electricity as the toaster.