Brake and Throttle modulation


I have a Miata that I track and I was hoping on getting some practice with this game.
I purchased a Miata and set my ABS to OFF, Steering Normal, Stability OFF, Traction OFF, just like my car is. When I started playing I have discovered that I have no throttle or brake modulation in this game. It is either on or off. I am playing on a PC without a sim rack (on my keyboard) but I was expecting that the game will kind of adapt the inputs as close as possible to real life scenario.
As soon as I was braking I was locking the wheels, I was spinning tires as soon as accelerating.
What kind of setting do I need to use to fix this issue if there is any fix at all?

Thank you!