On remote control I want to choose case and run it 20 or 200 times
You want to execute the case statement(s) multiple times for ONE switch press? Then, a for loop is needed.
I am making ping pong robot... player need to rest or change drill (case).
You can put
while(1)
{
}
at the end of the case, which will keep loop() busy, accomplishing nothing, until you reset the Arduino. But, I don't understand why you want to do that.