GTA V on PS5 controller question with a spoiler alert.

I've been playing GTA V on PC for years. I just bought a PS5 and need to learn the controller.

So I am playing GTA V in the mission where Michael and Franklin chase the boat and I get to the part where Michael needs to aim and fire a pistol while driving.

It says "Press R to Aim and (something else,) L1 (maybe) to fire.

What is R? I have been pressing every available button. I've googled. I've gone to the settings screen to try to discern WTF I am supposed to do. No luck.

By what key combination does one aim and shoot from a car, and where might those keys be.

If nothing else, repeating this mission 700 times has made me much better at driving using a controller.

I still miss keyboard and mouse.

Thanks!