How do you delete cookies on a MacBook?

You delete cookies through the preferences of the browser you are using. With Firefox, for example, you select "preferences" and then "privacy" and then "show cookies." At that point you have the option to delete some or all of your cookies. In Safari, you select "preferences" and "security" and then "show cookies" and you will have the same option to delete some or all of your cookies. Each browser has its own method of deleting cookies, but usually it can be found under the preferences panel.