Getting the feel for the cars in Gran Turismo Sport isn't easy, especially if you're uncomfortable with the driving controls.
Thankfully, changing your controls in the game is fairly straightforward.
You can change your driving controls from the GT Sport main menu.
First, select Options from the drop down, and then press R1 so that the menu screen jumps left to Controllers. Here is where you can change the settings for your controllers, including configuring your driving controls.
In this instance, we're going to change the driving controls for our Wireless Controller 1P, as I'm Player 1 and I'm using a standard PS4 controller.
This next screen will appear, which annotates each button the PS4 controller and what it current does. From here, you can simply select which button does which action, using the drop down options.
Make sure you press OK and everything should be changed to your satisfaction!