create a chronometer on excel

Hello everybody,

firstly I am sorry for my bad english level. I hope you will understand my problem. I have a chronometer on excel that I would like to modify by adding features. I attach the file.
I would like to time with intermediate times with an alarm when a time (target value) is reached.
For example: I start the timer: click ... click 5 sec. Click .... Click 3 sec. Click .... click. 2 sec
ok 2 sec is my target value, I have an alarm.

Ideally, knowing that it is difficult to have exactly the same value, it would be necessary to integrate a% close to the target value to consider that the target value is reached.

Is it possible?

Thank you all