Braking is not one part. It is pads, rotors, fluid, lines, and the electronics that decide how hard each wheel is allowed to stop.
Pads wear out, and rotors wear with them. Once a rotor is below its minimum thickness or has warped, it gets replaced rather than skimmed. Brake fluid absorbs water over time, which is what makes a pedal go soft long before anything visible is wrong.
That light means the system that stops your wheels locking has switched itself off. The brakes still work. The part that lets you steer while braking hard does not. It is most often a wheel speed sensor, and it gets diagnosed rather than guessed at.
A grinding noise is metal on metal, and it stopped being a pad job some time ago. A pedal that slowly sinks under your foot is a leak. Both get worse, and both get more expensive the longer they run.
If it has been hit and it also needs mechanical work, it does not need to go anywhere else.