Science allows us to gain more knowledge about a process or a phenomenon or a system. The scientific process starts with a why or a how (i.e., how does it happen, or why did it happen?) based on an observation of a process or a system.
To explain the observation, a hypothesis is formulated, which provides us with a potential explanation. The hypothesis is then tested with the help of evidence and if the evidence supports the hypothesis, it is considered verified. Else, the hypothesis is revised or may even be considered false.
Note that the observations can be direct (e.g., observing animals or plants) or indirect (e.g., observation of fossils). The evidence can be obtained through rigorous experimentation.
This is how science provides us with answers.
Hope this helps.