If you want to reuse the motor controller from the power wheels, you'll need to find it and understand it then connect an RF / BT or WiFi device to it. The easier approach would be to replace the motor controller
with a new one which allows you to easily connect to a computer. We suggest you use a serial motor controller
which would allow you to connect it to a Bluetooth, WiFi or RF transceiver
. Note that if you want to connect it to the computer, you will need to write code. You will need to read the manual for the controller as well as the transceiver to understand how to power the two and also make the necessary connections.