Teslas "virtual power plant" is only for Tesla Powerwall. There's no V2G capabilities in any Teslas to date, and I don't think there's even hardware support for it. The Tesla Cybertruck has V2L capability, so it might have the necessary hardware to do V2G with some software updates, but I kinda doubt it.

The Tesla "virtual power plant" does reserve some capacity for you, and technically you can charge your car with that. A single Tesla Powerwall is "only" 10kWh, and with inverter losses and such you're likely seeing closer to 8kWh of usable energy if you charge your car with it. You're probably much better off just using it to run your appliances so you mitigate some of the losses with more inverters in the mix.

Which is probably reasonable for most people, but still means if you go on a sudden road trip you are have to add power rather soon after leaving. (or you need to plan a head and go to charge only mode before leaving)