how can i confirm my selection using a button

ok, so just add another if around that:
void loop(){

if (button_pushed_state ==1 && locked_in flag = 0){
do all the digit stuff
read the button again}

else{
// button was pushed and not locked in
locked_in flag =1;
}
// do other code
// when all done:
locked_in flag = 0;

} // end void loop