Mapping pid

When to re mapping an input that doesnt supported by obd, we go to unit /choose the input like lt signal turn or high beam, then choose gpio, how to do that

I’m sorry, but I do not understand what you mean. Try to be more specific and detailed of what you are trying to achieve so I can help you.

Example, my car dont support pid for fuel level, the only way you can to use arduino that read voltage from fuel level gauge line, voltage from 0.5 to 5 volts, how to disply that on real dash

It does not support pids for turn signal, if i want to dispaly turn signal on realdash, can
i use arduino or rp to read this if the turn signal line is on from cluster wiring, then we send this input to real dash and show it on screen? How to do it

Use the RealDash CAN protocol to send the data from your Arduino to RealDash via serial/Bluetooth.

See RealDash CAN protocol here: