Need help with circuit design for current measurement of car starter
A shunt resistor is not a good idea in this case due to the high current.  The resistance you'd need to keep the voltage drop low and the dissipation reasonable would be so low that it would become highly impractical.

60 m&Omega; for 200 A is ridiculous, as even a few seconds thinking about it would have told you.  200 A x 60 m&Omega; = 12 V, which means all the voltage would be across the resistor with none left for the starter even if it could somehow draw 200 A under those conditions.  Clearly that can't work.  Second, the power dissipation is way out of range.  200 A thru 60 m&Omega; dissipates 2.4 kW!

At this current, I'd look for a hall effect current sensor.  Those sense the magnetic field caused by the current.