Do you mean getting the tablet to connect to the car's screen via WiFi? Why would you need to do that if it's connected via USB?A bit naive with Samsung/Android Auto going through Apple CarPlay.
In a Chevy Bolt, plugged into the USB, is there a way to get the tablet to use Android Auto Tablet through Wi_fi?
Do you mean using Android Auto to (for example) display nav on the car's screen while getting the nav data from the Internet via WiFi? If there's a WiFi hot spot you can connect to, I don't see why not. But where would there be a WiFi hotspot? Are you trying to use the OnStar hotspot?