C/C++ :: Time Delay Function - Timer Stop Counting If Any Key Pressed

My code is given below:

cout<<"1. runtim";
cout<<"2.tims";
cout<<"Your selection will be automatically neglected within (function to be inserted for time ) ";/* insert timer here */
cout<<"What kind of process u need to do";
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I have 2 questions

1.the timer function has to be such that when any key is pressed in between the specified time its has to stop its counting and go to the nest line and functions . i checked sleep function but if any key is pressed its does not break out of the sleep program and execute the next command

2.and if the timer has completely finished running then it has to skip few lines and execute the program .