Making a robot controlled by bluetooth raspberry pi 4 (using ios)

Hello, I am new to this and am trying to make a robot controlled by Bluetooth. I have looked around and seems to be many tutorials for Arduino but not many Raspberry pi 4. Raspberry pi 4 is BLE and wifi as well built in. My question is how to connect the app to my code over Bluetooth, I know that apparently the classic Bluetooth blocks don't work and I need to enable with code? Just don't know how. Also I'm using iphone not android.

You probably cannot use your iphone to do that yet. See what is available for ios here

It appears Bluetooth is not yet available for ios yet.