I'm really lost on this assignment and javascript in general. The simpler the code the better. Any help would be a blessing

Build a combination stopwatch and countdown timer. The application will allow the user to start either a stopwatch or a countdown timer. Only one timer should be able to run at a time.

These are the minimum required options for the full application:

User option to select which type of timer to run.

Stopwatch
-Start/Stop Button that reflects current state
-Reset button to restart
-Visual indication of current time elapsed in proper time format 00:00:00
-minutes, seconds, hundredths
Countdown Timer
-User input of time to countdown in proper time format
-00:00:00
-minutes, seconds, hundredths
-validate with regex
-Start/pause button
-Some form of notification when time has elapsed to notify user
-Visual indication of current time status in proper time format 00:00:00
-minutes, seconds, hundredths
-Maximum 10 minute countdown with entry validation for range
Debug Mode
-Visual output of states
-When buttons are clicked
-Time validation entry
-Indication of when a function has been called
on/off