Converter · runs in your browser
Convert the unit, and get the template too
Your sensor reports in the wrong unit. Here is the number converted, and the line to paste so it converts itself from now on.
Power is not energy, and this catches everyone
Watts is how fast you are using electricity right now. kWh is how much you have used over a period. You cannot convert one into the other with a multiplication — you need time.
In Home Assistant that is what the integration helper is for: it watches a power sensor and accumulates energy from it. If you want a device to appear in the Energy dashboard, that is the piece you are missing.
Questions people ask
Why does my energy sensor show watts instead of kWh?
Because power and energy are different things. Watts is how fast you are using it right now; kWh is how much you used over time. To go from one to the other you need an integration sensor, not a conversion.
Should I convert in the template or in Home Assistant?
If the device always reports the wrong unit, convert in the template. If it is only about how it is displayed, change the unit in the entity settings and leave the data alone.