Blynk and my custom built van

I have a obd2 chevy diesel van I have installed a bluetooth obd adapter on it that with the torque pro app allows me to read sensor data in real time, send the commands to read fault codes, and send a command to clear fault codes on the ECU I also have a volkswagen diesel car that i have a data cable to connect its ECU to my laptop and do the same things as the bluetooth adapter does wirelessly but it includes the ability to do things like activate the headlights without touching the switch or honk the horn with the laptop not the horn button but that is done in a totally different program called vcds so my question is could I use blynk to connect to my ECU with the bluetooth adapter and for example turn on the headlights from my phone since they are actually controlled by a relay when you move the switch to the on position the ECU receives the signal from the switch and then ot sends the signal to the relay to turn on the headlights and the relay sends power to the headlight bulb and your headlights come on so I am wanting to be able to skip the switch and send the command to the ECU wirelessly to activate the corresponding relay to operate the interior lights, the climate control system, the rear power seat that folds up to a bench seat or down to a bed, roll the power windows up and down and even start and stop the engine all from my phone and when the engine is running read engine sensors like coolant temp, battery voltage, rpm,and others and maybe even add sensors and relays to read the voltage on the auxiliary battery bank I have installed and when it gets down to a certain point if the engine is off actually start the engine and send the charge from the alternator to the auxiliary battery bank and put individual sensors and relays on each battery in the bank so that when that battery is 90% charged it can tell its relay to stop charging that battery doesnt get overcharged and when the sensor that reads the overall auxiliary battery bank voltage gets to say 90% it will tell the relay to stop charging the battery bank and shut the engine back off I also would like to power the tvs I installed in the back of the van on and off for example is that something I could possibly do with this app if I have the necessary hardware

Do you know the CanBus protocols for these vehicles, and have you done any experimentation with an MCU without Blynk to control these devices?
If you can get with working by sending commands to an Arduino, NodeMCU or ESP32 without Blynk then yes, you should be able to do these things via the Blynk app as well.