You can find your name-server setting with the company you bought your domain from. Some companies that sell domains include GoDaddy, Domain.com, Dreamhost, Bluehost, etc.
If you don't know where you bought your domain, you can look it up using this link.
Each company is different, so if you cannot find your name-server settings in their platform, reach out to their customer support and they will show you where to go.
Once you have your name-server settings open, read this article to finish pointing to Futurestay.