Buddhism is a non-theistic spiritual path that helps us cultivate more positive mental states, including our natural awareness and emotional warmth. This allows us to live more meaningful and fulfilling lives. Its ultimate goal is 'Enlightenment' or waking up - direct insight into the nature of reality. It gives us a tried and tested set of practices and teachings that help us move towards Enlightenment by a process of spiritual growth.
For thousands of years people have found that the practices of Buddhism really do work, leading to better mental states, clearer vision, and the ability to live more authentic lives. But the Buddha himself said: don't take my word for it - try it for yourself. Judge by your own experience and see if it works.