These are things which are not confirmed, therefore please take everything with a grain of salt.
The universe started out by something most of the world agrees is the big bang. If this theory is true then we think about how are we considered alive. If people came from the earth and the earth came from particles then that means we came from particles. If we do consider ourselves alive then we don’t understand what does it mean and how did we become living when we are made from non-living particles.
People also know that one day like all things, this universe will end, if this is true then that means none of the things we do matter, every embarrassment, crime, wrong thing we have felt or done won’t matter either. We all will die and since nothing will control it and nothing will matter, we, humans, who are positive in nature, should try to do the best we can to change the life of ourselves, better if we change the life of others and even better if we can change the entire world by helping in human development.
Scientists even say that we might be stimulated, we feel we are real but are actually controlled, same goes in this case; we should do the best we can to bring change as that is our purpose and change is nature. If nature wants, we may be a negative change to balance a positive change.
At this stage, our end is far beyond our lives, we have got other things to worry about. Even if nothing is real and nothing matters, why not try to save a planet which will also eventually die just for fun and for the sake of being human. We are the senses of the universe to feel itself.
Think of it this way, In a game of tic tac toe, it is almost certain you will draw the game but you still play the game just for fun. Life is a game that you play until you are bored or until you want to quit. If you are bored at the beginning from playing a game you want to change it with power ups, variations to make it interesting. Similarly we develop, increase our knowledge of the universe and socially interact with other players, to play the game better.