(Image source from: Learn from past experience)
The future is nothing but the result of present day action. A golden rule for happiness in life is to learn from the past and make the present so beautiful that the future is naturally take care of. In life, it's necessary to focus on the present as the past has been lived and done with. Besides, the future is beyond us. We cannot change what happened in the past, so there is no point dwelling on it, unless you are thinking of not repeating past mistakes.
(AW: Pratima Tigga)