Every case is different, but it generally takes just over a week for Google to know your business exists and (if you have a physical store) for this to show on their maps. This means people can start making their way to your store when they haven't met you before! But to have your website ranking well on Google often takes 4 to 12 months, depending on the intensity of your competition. For example, it would be easy to rank in the top ten for an ice bar (if you opened one), but ranking for accommodation in the CBD would be a whole other story!