When someone clicks on your ad (the blue headline of a text ad or on your banner), Google Ads will count it as a click. When people click your ads, they will be redirected to your site. This way we bring you traffic to your store, from then on it's your duty to convert them. Google will charge you a specific amount per click. You can calculate your cost per click by dividing your total amount charged by Google by the number of clicks acquired by your ad. If you have any doubt about your campaign's performance, contact your account manager for feedback. You can check how many clicks you have had and more data about the performance of your campaigns, on your Clever dashboard.
More info about cost-per-click on Google.
How much should I pay per click?