URL parameters for window.location.search

I would like to deploy a site and would like to know if and how I can use URL parameters (const urlParams = new URLSearchParams(queryString):wink:
i.e: www.XXXXX.com/index.html?clientID=???

This way each client gets it’s own address and the site knows what content to display according to the clientID.
How can I do it on your system that generates a random url for the deployment.

There’s also a fixed URL: Custom domains | Netlify Docs