TimeManager time tracking

Which general topic do you have

Hi all,
I’m searching a time tracking tool and would like to give TimeManager a try.
But I’m missing a for me very important function: How can I start the tracking of time?
I would expect to have a start and stop button.
Or can I only fill in the used time for a task?
If TimeManager does not work this way, can you recommend a tool where I can track the time needed for different projects and export it later for every month?