Depends on your provider system.
On most energy meters in the world, there is a 1kWh blinking light. There are a few blink counter systems integrated into home assistant.
If you are in europe, P1 port DSMR energy monitor is king. I get multi-phase, self-powered incoming energy monitor for 15€. It is an international standard protocol in much of central and northern europe.
If you want live current and live in the US: use a current clamp system. You can build your own using ESPHome and off the shelf current clamps. I have some circuits drawn up for rectifying the AC current to DC voltage which is much easier than trying to sample the waveform.
For a very complete, but cloud solution, this is one of the best products as far as price point https://shop.emporiaenergy.com/collections/in-panel-energy-monitors/products/gen-2-emporia-vue-with-16-sensors-bundle