Time controlled light

OK guys I am totally confused. If I have simple values of time from RTC (from 00.00 to 23.59) I expect an option to trigger on something at the specific time and switch it of also at the specific time. And now you are telling me that this is not possible...
As I have said I am not good in English so might be I misunderstood you even if I read your answers a lot of times.
Guys can you explain me in more simple manner that even me could understood :disappointed_relieved: because I really do not believe that this is not possible. Thanks.