You can not change the entities icon in this way.
I think your options are (but I will be corrected when wrong) either;
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look for a matching icon on Material Design Icons and hope it is supported by HomeAssistant
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use customise.yaml as indicated here My own icons - #9 by petro
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create your own icon in svg format (optimised) using Inkscape
add this to your own icon set
example GitHub - arallsopp/hass-hue-icons: Additional vector icons for home assistant to model Philips Hue bulbs and fixtures.
If you want to add many custom icons the last option would be the way forward. If you search on Github for hass icons or home assistant icons you will find many more repositories with custom icons.