Thank you for reaching out! From a technical standpoint, any URL from your website which has the affiliate referral tracking variable in it, is a referral URL.
So, whichever page a referred visitor lands on via a referral URL will generate a visit, which you can see in SliceWP > Visits.
You can also change the default referral URL that’s shown to affiliates in their account, by setting this value in the “Affiliate Default Referral URL” option from SliceWP > Settings > General > Pages Settings.
Thank you and best wishes,