how to make your webpage create a cookie when a checkbox is clicked [duplicate]

i want to make my webpage to create a cookie when a user clicks on a checkbox
For example, if a user wants to login and they click the 'remember me' checkbox and clicks the 'submit' button it will fetch the username and password and put them as cookies
and also i will like to know how to retrieve the cookies for later use BTW i would like if the cookie lasts forever