First Party and Third Party Cookie

I want to create a analysis project (just like google analysis),for getting conversion rate and track visitor count.How can we create first party cookie and third party cookie using php.Actually, how can we identify our third party and first party cookie.Need to follow any type of standard for identify them?if anybody k开发者_运维知识库now please give me some idea about it...please

• first-party cookies which are set by the web server of the visited page and share the same domain • third-party cookies stored by a different domain to the visited page's domain. This can happen when the webpage references a file, such as JavaScript, located outside its domain

Don't have source beyond the fact that I pulled from some GDPR documentation last week.