Cab of an old Soviet-built diesel locomotive in east Germany, now in the museum in Dresden (DR 120 338–9). What looks like a steering wheel of a car and maybe they even used a part from the car industry is the equivalent to the gas pedal in a car. You turn it right to control the speed and power of the engine. The handle to the right is the air brake valve.
As a more modern example here is the cab of an Austrian class 2016 diesel locomotive, there is no more steering wheel, one of the little handles to the left has this function. The driver now has a clear “desk” where a paper timetable could be put (though they normally use electronic timetables, the screen for that can be seen on the right).