Ajude-me com Marketing

Hi, i have a website of my team with a direct selling company, and i would like to create refereal links. any one of my team will a page to register, and after that have is own Refer Link ( based on an ID that he have to write on the registration. ) after that, they share the link for the people to access the website, and if someone register ( contact form 7 or other form plugins / newsletter forms ) i will know that the person camed from that link ( id ). Also if possible, that after we share the link, it will have a cookie for 7 days, that if that person come later to my website, will still be a refer from that person. And also a page where the users can see the statistics ( clicks and conversion )