Creating a Ble application, WIN API

We need to write a protocol for communication between the device and the computer, so that we have data transmission, bytes, etc., in the future, coeficents, etc., will be transmitted, also for this we need an interface so that we can enter the necessary data. The protocol is made under windows 32 bit, so the win api is used. Now the main thing is to connect and make methods for sending and receiving from the can busю. you need to do it through a terminal connection