Why are there even 3 pedals on a car?

The 3rd one is for clutch, as in changing gears.

I have never seen that pedal before. Is this some American thing I'm too asian to understand?

It's usually for manual gears

Clutch is for a manual transmission, you push it down when you shift and it connects and disconnects the engine’s power from the transmission. If you tried shifting without pushing the clutch, you’d ruin your manual transmission

Algebra

A

A is the only valid pedal

You don’t need the other two

Why does the shoe on the right look like an animated character's finger tip

it has to be c and then b

In the wise words of Spongebob: "FLOOR IT!!!"

*brake not break